import java.util.*;
import java.util.zip.*;
import java.util.List;
import java.util.regex.*;
import java.util.concurrent.*;
import java.util.concurrent.atomic.*;
import java.util.concurrent.locks.*;
import java.util.function.*;
import javax.swing.*;
import javax.swing.event.*;
import javax.swing.text.*;
import javax.swing.table.*;
import java.io.*;
import java.net.*;
import java.lang.reflect.*;
import java.lang.ref.*;
import java.lang.management.*;
import java.security.*;
import java.security.spec.*;
import java.awt.*;
import java.awt.event.*;
import java.awt.image.*;
import java.awt.geom.*;
import javax.imageio.*;
import java.math.*;
// G22SkeletonToMesh converts a skeleton (thinned image region)
// to a mesh.

// A "mesh" is a set of points ("anchors") connected through curves.
// More docs at G22Mesh

import java.awt.geom.*;
import static x30_pkg.x30_util.DynamicObject;
import java.text.NumberFormat;

class main {

static class G22SkeletonToMesh<Img extends WidthAndHeight> extends G22Mesh implements Steppable , IFieldsToList{
  IImageRegion<Img> region;
  G22SkeletonToMesh() {}
  G22SkeletonToMesh(IImageRegion<Img> region) {
  this.region = region;}
  public String toString() { return shortClassName_dropNumberPrefix(this) + "(" + region + ")"; }public Object[] _fieldsToList() { return new Object[] {region}; }

   final public G22SkeletonToMesh<Img > setDebug(boolean debug){ return debug(debug); }
public G22SkeletonToMesh<Img > debug(boolean debug) { this.debug = debug; return this; }  final public boolean getDebug(){ return debug(); }
public boolean debug() { return debug; }
 boolean debug = false;
   final public G22SkeletonToMesh<Img > setDebugDroppingUnnecessaryAnchors(boolean debugDroppingUnnecessaryAnchors){ return debugDroppingUnnecessaryAnchors(debugDroppingUnnecessaryAnchors); }
public G22SkeletonToMesh<Img > debugDroppingUnnecessaryAnchors(boolean debugDroppingUnnecessaryAnchors) { this.debugDroppingUnnecessaryAnchors = debugDroppingUnnecessaryAnchors; return this; }  final public boolean getDebugDroppingUnnecessaryAnchors(){ return debugDroppingUnnecessaryAnchors(); }
public boolean debugDroppingUnnecessaryAnchors() { return debugDroppingUnnecessaryAnchors; }
 boolean debugDroppingUnnecessaryAnchors = false;
   final public G22SkeletonToMesh<Img > setAutoSimplify(boolean autoSimplify){ return autoSimplify(autoSimplify); }
public G22SkeletonToMesh<Img > autoSimplify(boolean autoSimplify) { this.autoSimplify = autoSimplify; return this; }  final public boolean getAutoSimplify(){ return autoSimplify(); }
public boolean autoSimplify() { return autoSimplify; }
 boolean autoSimplify = true;
  
  // TEMPORARY DATA
  
  IterableIterator<Pt> regionIterator;
  List<WorkItem> queue = new ArrayList();
  PtSet pointsSeen = new PtSet();
  
  // p is a point in 3x3 neighborhood of anchor
  static class WorkItem implements IFieldsToList{
  Anchor anchor;
  Pt p;
  WorkItem() {}
  WorkItem(Anchor anchor, Pt p) {
  this.p = p;
  this.anchor = anchor;}
  public String toString() { return shortClassName_dropNumberPrefix(this) + "(" + anchor + ", " + p + ")"; }public Object[] _fieldsToList() { return new Object[] {anchor, p}; }
}

  public boolean step() {
    // first, initialize iterator
    if (regionIterator == null)
      regionIterator = region.pixelIterator();
    
    // then check queue for work
    if (nempty(queue)) {
      WorkItem work = popLast(queue);
      
      Pt p = work.p;
      
      PtBuffer curvePoints = new PtBuffer();
      curvePoints.add(work.anchor.pt); // add anchor to path
      Anchor endAnchor = null;

      if (debug) print("Exploring from " + work.anchor.pt + " / " + p);
      
      while  (true) { ping(); 
        if (debug) print("Curve point " + p);
        curvePoints.add(p);
        
        // did we hit another anchor?
        endAnchor = anchorMap.get(p);
        if (endAnchor != null) {
          if (debug) print("Hit anchor " + endAnchor);
          break;
        }

        // check if we visited this point already
        if (!pointsSeen.add(p)) {
          if (l(curvePoints) == 2)
            return true; // It's a 1-pixel curve anyway, just forget it
          else
            // If this is an actual thing, we should make a proper anchor here (splitting existing curves).
            // I don't think it's actually a thing though
            warn("Surprising seen point (" + curvePoints + "). Adding as anchor");
          break;
        }
        
        PtBuffer branches = unexploredPointsAround(p);
        
        // line ends or branches - same thing for us, it means our curve ends and we create a new anchor here
        if (l(branches) != 1) {
          if (debug) print("Branch count: " + l(branches));
          break;
        } else
          p = first(branches); // curve continues
      }

      if (endAnchor == null)
        endAnchor = newAnchor(p);
        
      addCurve(new Curve(work.anchor, endAnchor, curvePoints));
      return true;
    }
    
    // finally look for next point in region
    if (regionIterator.hasNext()) {
      Pt p = regionIterator.next();
      
      // check if point already seen, otherwise mark as seen
      if (!pointsSeen.add(p)) return true;
      
      // new point - save as anchor
      newAnchor(p);
      return true;
    }
    
    // last step, simplify
      
    if (autoSimplify) simplify();
    return false;
  }

  Anchor newAnchor(Pt p) {  
    Anchor anchor = new Anchor(l(anchorMap)+1, p);
    anchorMap.put(p, anchor);
    //anchors.add(anchor);
      
    // explore in all directions
    for (Pt p2 : unexploredPointsAround(p))
      queue.add(new WorkItem(anchor, p2));
      
    return anchor;
  }
  
  PtBuffer unexploredPointsAround(Pt p) {
    PtBuffer out = new PtBuffer();
    for (int dir = 1; dir <= 8; dir++) {
      Pt p2 = onePathDirection(p, dir);
      if (region.contains(p2) && !pointsSeen.contains(p2))
        out.add(p2);
    }
    return out;
  }
  
  boolean simplify() {
    return 0 != stepAll(combineSteppables_dontDropEnded(
      () -> dropLengthOneCurves(),
      () -> dropShortLoops(),
      () -> dropUnnecessaryAnchors()));
  }
  
  // drops very short curves connecting a node to itself
  // returns true if anything changed
  boolean dropShortLoops() {
    int n = l(curves);
    for (Curve curve : cloneList(curves)) {
      if (curve.start != curve.end) continue;
      if (curve.length() > 3) continue;
      
      if (debug) print("Removing short loop: " + curve);
      removeCurve(curve);
    }
    
    return l(curves) < n;
  }
      
  // returns true if anything changed
  boolean dropLengthOneCurves() {
    int n = l(anchorMap);
    for (Curve curve : cloneList(curves)) {
      if (curve.length() != 1) continue;
      
      // Decide which anchor to keep
      boolean keepStartAnchor = curve.start.arity() >= curve.end.arity();
      
      // Forget curve
      removeCurve(curve);
      
      // Merge the less important (defined as: less connected) anchor into the other one
      if (keepStartAnchor)
        mergeAnchor(curve.end, curve.start);
      else
        mergeAnchor(curve.start, curve.end);
    }
    return l(anchorMap) < n;
  }
  
  void removeCurve(Curve curve) {
    curves.remove(curve);
    curve.start.outgoingCurves.remove(curve);
    curve.end.incomingCurves.remove(curve);
  }
  
  // moves a1's connections to a2, deletes a1
  void mergeAnchor(Anchor a1, Anchor a2) {
    if (debug) printVarsInMultipleLines("mergeAnchor", "a1", a1, "a2", a2);
    
    for (Curve curve : a1.outgoingCurves) {
      // first step is now going from a2 to a1
      curve.path.insertStep(0, ptMinus(a1.pt, a2.pt));
      curve.path.origin(a2.pt);
      curve.start = a2;
      a2.outgoingCurves.add(curve);
    }
    
    for (Curve curve : a1.incomingCurves) {
      // last step is now going from a1 to a2
      curve.path.addStep(ptMinus(a2.pt, a1.pt));
      curve.end = a2;
      a2.incomingCurves.add(curve);
    }
    
    anchorMap.remove(a1.pt);
  }
  
  // returns true if anything changed
  boolean dropUnnecessaryAnchors() {
    int n = l(anchorMap);
    for (Anchor anchor : cloneValues(anchorMap)) {
      if (anchor.arity() != 2) continue;
      if (anchor.isRingAnchor()) continue;
      
      // It's a non-branching anchor sitting on a curve - we can drop it.
      if (debugDroppingUnnecessaryAnchors) print("Dropping " + anchor);
      
      // This list will have length 2
      List<Curve> curves = concatLists(anchor.incomingCurves, anchor.outgoingCurves);
      
      // Find the endpoints of the new curve (either 1 or 2 anchors)
      Set<Anchor> anchors = concatMapToSet(curves, c -> c.anchors());
      anchors.remove(this);
      
      if (debugDroppingUnnecessaryAnchors) printVarsInMultipleLines("curves", curves, "anchors", anchors);
      
      // Collect points for merged curve
      
      // Process curve 1, optionally reverse it so it does NOT start at the middle anchor 
      Curve curve1 = first(curves);
      removeCurve(curve1);
      List<Pt> points1 = curve1.path.pointList();
      if (eq(first(points1), anchor.pt)) reverseInPlace(points1);
      
      // Process curve 2, optionally reverse it so it DOES start at the middle anchor 
      Curve curve2 = second(curves);
      removeCurve(curve2);
      List<Pt> points2 = curve2.path.pointList();
      if (!eq(first(points2), anchor.pt)) reverseInPlace(points2);
      
      // Drop overlapping point, append points2 to points1
      assertEquals(anchor.pt, popLast(points1));
      List<Pt> points = points1;
      addAll(points, points2);
      
      Anchor anchor1 = assertNotNull(anchorMap.get(first(points)));
      Anchor anchor2 = assertNotNull(anchorMap.get(last(points)));
      
      if (debugDroppingUnnecessaryAnchors) printVarsInMultipleLines("anchor", anchor, "anchor1", anchor1, "anchor2", anchor2);
      
      anchorMap.remove(anchor.pt);
      addCurve(new Curve(anchor1, anchor2, points));
    }
    
    return l(anchorMap) < n;
  }
  
  void addCurve(Curve curve) {
    curves.add(curve);
  }
}
static String shortClassName_dropNumberPrefix(Object o) {
  return dropNumberPrefix(shortClassName(o));
}


static boolean nempty(Collection c) {
  return !empty(c);
}

static boolean nempty(CharSequence s) {
  return !empty(s);
}

static boolean nempty(Object[] o) { return !empty(o); }
static boolean nempty(byte[] o) { return !empty(o); }
static boolean nempty(int[] o) { return !empty(o); }

static boolean nempty(BitSet bs) { return !empty(bs); }

static boolean nempty(Map m) {
  return !empty(m);
}

static boolean nempty(Iterator i) {
  return i != null && i.hasNext();
}


static boolean nempty(IMultiMap mm) { return mm != null && mm.size() != 0; }



static boolean nempty(Object o) { return !empty(o); }







static boolean nempty(LongBuffer b) { return b != null && !b.isEmpty(); }



static boolean nempty(Rect r) { return r != null && r.w != 0 && r.h != 0; }







static <A> A popLast(List<A> l) {
  return liftLast(l);
}

static <A> List<A> popLast(int n, List<A> l) {
  return liftLast(n, l);
}




static volatile StringBuffer local_log = new StringBuffer(); // not redirected




static boolean printAlsoToSystemOut = true;

static volatile Appendable print_log = local_log; // might be redirected, e.g. to main bot

// in bytes - will cut to half that
static volatile int print_log_max = 1024*1024;
static volatile int local_log_max = 100*1024;

static boolean print_silent = false; // total mute if set

static Object print_byThread_lock = new Object();
static volatile ThreadLocal<Object> print_byThread; // special handling by thread - prefers F1<S, Bool>
static volatile Object print_allThreads;
static volatile Object print_preprocess;

static void print() {
  print("");
}

static <A> A print(String s, A o) {
  print(combinePrintParameters(s, o));
  return o;
}

// slightly overblown signature to return original object...
static <A> A print(A o) {
  ping_okInCleanUp();
  if (print_silent) return o;
  String s = o + "\n";
  print_noNewLine(s);
  return o;
}

static void print_noNewLine(String s) {
  
  try {
    Object f = getThreadLocal(print_byThread_dontCreate());
    if (f == null) f = print_allThreads;
      if (f != null)
        // We do need the general callF machinery here as print_byThread is sometimes shared between modules
        if (isFalse(
          
            f instanceof F1 ? ((F1) f).get(s) :
          
          callF(f, s))) return;
  } catch (Throwable e) {
    System.out.println(getStackTrace(e));
  }
  

  print_raw(s);
}

static void print_raw(String s) {
  
  if (print_preprocess != null) s = (String) callF(print_preprocess, s);
  s = fixNewLines(s);
  
  Appendable loc = local_log;
  Appendable buf = print_log;
  int loc_max = print_log_max;
  if (buf != loc && buf != null) {
    print_append(buf, s, print_log_max);
    loc_max = local_log_max;
  }
  if (loc != null) 
    print_append(loc, s, loc_max);
  
  
  if (printAlsoToSystemOut)
    System.out.print(s);
  
  
  vmBus_send("printed", mc(), s);
  
}

static void print_autoRotate() {
  
}








//sbool ping_actions_shareable = true;
static volatile boolean ping_pauseAll = false;
static int ping_sleep = 100; // poll pauseAll flag every 100
static volatile boolean ping_anyActions = false;
static Map<Thread, Object> ping_actions = newWeakHashMap();
static ThreadLocal<Boolean> ping_isCleanUpThread = new ThreadLocal();

// always returns true
static boolean ping() {
  //ifdef useNewPing
  newPing();
  //endifdef
  if (ping_pauseAll || ping_anyActions) ping_impl(true /* XXX */);
  //ifndef LeanMode ping_impl(); endifndef
  return true;
}

// returns true when it slept
static boolean ping_impl(boolean okInCleanUp) { try {
  if (ping_pauseAll && !isAWTThread()) {
    do
      Thread.sleep(ping_sleep);
    while (ping_pauseAll);
    return true;
  }
  
  if (ping_anyActions) { // don't allow sharing ping_actions
    if (!okInCleanUp && !isTrue(ping_isCleanUpThread.get()))
      failIfUnlicensed();
    Object action = null;
    synchronized(ping_actions) {
      if (!ping_actions.isEmpty()) {
        action = ping_actions.get(currentThread());
        if (action instanceof Runnable)
          ping_actions.remove(currentThread());
        if (ping_actions.isEmpty()) ping_anyActions = false;
      }
    }
    
    if (action instanceof Runnable)
      ((Runnable) action).run();
    else if (eq(action, "cancelled"))
      throw fail("Thread cancelled.");
  }

  return false;
} catch (Exception __e) { throw rethrow(__e); } }




static int l(Object[] a) { return a == null ? 0 : a.length; }
static int l(boolean[] a) { return a == null ? 0 : a.length; }
static int l(byte[] a) { return a == null ? 0 : a.length; }
static int l(short[] a) { return a == null ? 0 : a.length; }
static int l(long[] a) { return a == null ? 0 : a.length; }
static int l(int[] a) { return a == null ? 0 : a.length; }
static int l(float[] a) { return a == null ? 0 : a.length; }
static int l(double[] a) { return a == null ? 0 : a.length; }
static int l(char[] a) { return a == null ? 0 : a.length; }
static int l(Collection c) { return c == null ? 0 : c.size(); }

static int l(Iterator i) { return iteratorCount_int_close(i); } // consumes the iterator && closes it if possible

static int l(Map m) { return m == null ? 0 : m.size(); }
static int l(CharSequence s) { return s == null ? 0 : s.length(); }
static long l(File f) { return f == null ? 0 : f.length(); }






  static int l(IMultiMap mm) { return mm == null ? 0 : mm.size(); }













  static int l(LongBuffer b) { return b == null ? 0 : b.size(); }



  static int l(AppendableChain a) { return a == null ? 0 : a.size; }






static boolean warn_on = true;
static ThreadLocal<List<String>> warn_warnings = new ThreadLocal();

static void warn(String s) {
  if (warn_on)
    print("Warning: " + s);
}

static void warn(String s, List<String> warnings) {
  warn(s);
  if (warnings != null)
    warnings.add(s);
  addToCollection(warn_warnings.get(), s);
}



static Object first(Object list) {
  return first((Iterable) list);
}


static <A> A first(List<A> list) {
  return empty(list) ? null : list.get(0);
}

static <A> A first(A[] bla) {
  return bla == null || bla.length == 0 ? null : bla[0];
}

static <A, B> Pair<A, B> first(Map<A, B> map) {
  return mapEntryToPair(first(entrySet(map)));
}

static <A, B> Pair<A, B> first(MultiMap<A, B> mm) {
  if (mm == null) return null;
  var e = first(mm.data.entrySet());
  if (e == null) return null;
  return pair(e.getKey(), first(e.getValue()));
}


static <A> A first(IterableIterator<A> i) {
  return first((Iterator<A>) i);
}


static <A> A first(Iterator<A> i) {
  return i == null || !i.hasNext() ? null : i.next();
}

static <A> A first(Iterable<A> i) {
  if (i == null) return null;
  Iterator<A> it = i.iterator();
  return it.hasNext() ? it.next() : null;
}

static Character first(String s) { return empty(s) ? null : s.charAt(0); }
static Character first(CharSequence s) { return empty(s) ? null : s.charAt(0); }


static <A, B> A first(Pair<A, B> p) {
  return p == null ? null : p.a;
}




static Byte first(byte[] l) { 
  return empty(l) ? null : l[0];
}




static byte first(ByteBuffer buf) {
  return buf.get(0);
}


static <A> A first(A[] l, IF1<A, Boolean> pred) {
  return firstThat(l, pred);
}

static <A> A first(Iterable<A> l, IF1<A, Boolean> pred) {
  return firstThat(l, pred);
}

static <A> A first(IF1<A, Boolean> pred, Iterable<A> l) {
  return firstThat(pred, l);
}


static <A> A first(AppendableChain<A> a) {
  return a == null ? null : a.element;
}




static Pt onePathDirection(int index) {
  return onePathDirections()[index];
}

static Pt onePathDirection(Pt p, int index) {
  return ptPlus(p, onePathDirections()[index]);
}


// returns number of steps
static long stepAll(Steppable s) {
  long steps = 0;
  if (s != null)
    while  (s.step()) { ping(); ++steps; }
  return steps;
}



static Steppable combineSteppables_dontDropEnded(Iterable<? extends Steppable> steppables) {
  List<? extends Steppable> steppablesList = nonNulls(steppables);
  
  return () -> {
    boolean change = false;
    for (var s : steppablesList)
      change |= s.step();
    return change;
  };
}

static <A extends Steppable> Steppable combineSteppables_dontDropEnded(A... steppables) {
  return combineSteppables(asList(steppables));
}


static <A> ArrayList<A> cloneList(Iterable<A> l) {
  return l instanceof Collection ? cloneList((Collection) l) : asList(l);
}

static <A> ArrayList<A> cloneList(Collection<A> l) {
  if (l == null) return new ArrayList();
  synchronized(collectionMutex(l)) {
    return new ArrayList<A>(l);
  }
}


// Use like this: printVarsInMultipleLines(+x, +y);
// Or: printVarsInMultipleLines("bla", +x);
// Or: printVarsInMultipleLines bla(+x);
static void printVarsInMultipleLines(Object... params) {
  print(renderVarsInMultipleLines(params));
}


static Pt ptMinus(Pt a, Pt b) {
  if (b == null) return a;
  return new Pt(a.x-b.x, a.y-b.y);
}


static <A, B> List<B> cloneValues(Map<A, B> map) {
  return cloneList(values(map));
}


static <A> List<A> concatLists(Iterable<A>... lists) {
  List<A> l = new ArrayList();
  if (lists != null) for (Iterable<A> list : lists)
    addAll(l, list);
  return l;
}

static <A> List<A> concatLists(Collection<? extends Iterable<A>> lists) {
  List<A> l = new ArrayList();
  if (lists != null) for (Iterable<A> list : lists)
    addAll(l, list);
  return l;
}



static <A, B, C extends Iterable<B>> Set<B> concatMapToSet(Iterable<A> l, IF1<A, C> f) {
  Set<B> set = new HashSet();
  if (l != null)
    for (var a : l)
      addAll(set, f.get(a));
  return set;
}

static <A, B, C extends Iterable<B>> Set<B> concatMapToSet(IF1<A, C> f, Iterable<A> l) {
  return concatMapToSet(l, f);
}

static <A, B, C extends Iterable<B>> Set<B> concatMapToSet(IF1<A, C> f, A[] l) {
  Set<B> set = new HashSet();
  if (l != null)
    for (var a : l)
      addAll(set, f.get(a));
  return set;
}


static boolean eq(Object a, Object b) {
  return a == b || a != null && b != null && a.equals(b);
}


// a little kludge for stuff like eq(symbol, "$X")
static boolean eq(Symbol a, String b) {
  return eq(str(a), b);
}



static <A> List<A> reverseInPlace(List<A> l) {
  return reverseList(l);
}


static <A> A second(List<A> l) {
  return get(l, 1);
}

static <A> A second(Iterable<A> l) {
  if (l == null) return null;
  Iterator<A> it = iterator(l);
  if (!it.hasNext()) return null;
  it.next();
  return it.hasNext() ? it.next() : null;
}

static <A> A second(A[] bla) {
  return bla == null || bla.length <= 1 ? null : bla[1];
}


static <A, B> B second(Pair<A, B> p) {
  return p == null ? null : p.b;
}






static char second(String s) {
  return charAt(s, 1);
}




static <A> A assertEquals(Object x, A y) {
  return assertEquals("", x, y);
}

static <A> A assertEquals(String msg, Object x, A y) {
  if (assertVerbose()) return assertEqualsVerbose(msg, x, y);
  if (!(x == null ? y == null : x.equals(y)))
    throw fail((msg != null ? msg + ": " : "") + y + " != " + x);
  return y;
}




static <A, B extends A> void addAll(Collection<A> c, Iterable<B> b) {
  if (c != null && b != null) for (A a : b) c.add(a);
}

static <A, B extends A> boolean addAll(Collection<A> c, Collection<B> b) {
  return c != null && b != null && c.addAll(b);
}

static <A, B extends A> boolean addAll(Collection<A> c, B... b) {
  return c != null && b != null && c.addAll(Arrays.asList(b));
}



static <A, B> Map<A, B> addAll(Map<A, B> a, Map<? extends A,? extends B> b) {
  if (a != null && b != null) a.putAll(b);
  return a;
}

static <A extends Container> A addAll(A c, Collection<? extends Component> components) {
  return addComponents(c, components);
}

static <A extends Container> A addAll(A c, Component... components) {
  return addComponents(c, components);
}


static <A> A assertNotNull(A a) {
  assertTrue(a != null);
  return a;
}

static <A> A assertNotNull(String msg, A a) {
  assertTrue(msg, a != null);
  return a;
}




static <A> A last(List<A> l) {
  return empty(l) ? null : l.get(l.size()-1);
}

static char last(String s) {
  return empty(s) ? '#' : s.charAt(l(s)-1);
}

static byte last(byte[] a) {
  return l(a) != 0 ? a[l(a)-1] : 0;
}

static int last(int[] a) {
  return l(a) != 0 ? a[l(a)-1] : 0;
}

static double last(double[] a) {
  return l(a) != 0 ? a[l(a)-1] : 0;
}

static <A> A last(A[] a) {
  return l(a) != 0 ? a[l(a)-1] : null;
}

static <A> A last(Iterator<A> it) {
  A a = null;
  while  (it.hasNext()) { ping(); a = it.next(); }
  return a;
}

static <A> A last(Collection<A> l) {
  if (l == null) return null;
  if (l instanceof List) return (A) last((List) l);
  if (l instanceof SortedSet) return (A) last((SortedSet) l);
  Iterator<A> it = iterator(l);
  A a = null;
  while  (it.hasNext()) { ping(); a = it.next(); }
  return a;
}

static <A> A last(SortedSet<A> l) {
  return l == null ? null : l.last();
}






static byte last(ByteBuffer buf) {
  return buf.get(buf.size()-1);
}









static AutoCloseable tempInterceptPrintIfNotIntercepted(F1<String, Boolean> f) {
  return print_byThread().get() == null ? tempInterceptPrint(f) : null;
}


static String dropNumberPrefix(String s) {
  return dropFirst(s, indexOfNonDigit(s));
}


static String shortClassName(Object o) {
  if (o == null) return null;
  Class c = o instanceof Class ? (Class) o : o.getClass();
  String name = c.getName();
  return shortenClassName(name);
}


static boolean empty(Collection c) { return c == null || c.isEmpty(); }
static boolean empty(Iterable c) { return c == null || !c.iterator().hasNext(); }
static boolean empty(CharSequence s) { return s == null || s.length() == 0; }
static boolean empty(Map map) { return map == null || map.isEmpty(); }
static boolean empty(Object[] o) { return o == null || o.length == 0; }
static boolean empty(BitSet bs) { return bs == null || bs.isEmpty(); }


static boolean empty(Object o) {
  if (o instanceof Collection) return empty((Collection) o);
  if (o instanceof String) return empty((String) o);
  if (o instanceof Map) return empty((Map) o);
  if (o instanceof Object[]) return empty((Object[]) o);
  if (o instanceof byte[]) return empty((byte[]) o);
  if (o == null) return true;
  throw fail("unknown type for 'empty': " + getType(o));
}


static boolean empty(Iterator i) { return i == null || !i.hasNext(); }

static boolean empty(double[] a) { return a == null || a.length == 0; }
static boolean empty(float[] a) { return a == null || a.length == 0; }
static boolean empty(int[] a) { return a == null || a.length == 0; }
static boolean empty(long[] a) { return a == null || a.length == 0; }
static boolean empty(byte[] a) { return a == null || a.length == 0; }
static boolean empty(short[] a) { return a == null || a.length == 0; }




static boolean empty(IMultiMap mm) { return mm == null || mm.size() == 0; }


static boolean empty(File f) { return getFileSize(f) == 0; }








static boolean empty(LongBuffer b) { return b == null || b.isEmpty(); }



static boolean empty(Rect r) { return !(r != null && r.w != 0 && r.h != 0); }





static boolean empty(AppendableChain c) { return c == null; }



static <A> A liftLast(List<A> l) {
  if (empty(l)) return null;
  int i = l(l)-1;
  A a = l.get(i);
  l.remove(i);
  return a;
}

static <A> List<A> liftLast(int n, List<A> l) {
  int i = l(l)-n;
  List<A> part = cloneSubList(l, i);
  removeSubList(l, i);
  return part;
}


static String combinePrintParameters(String s, Object o) {
  return (endsWithLetterOrDigit(s) ? s + ": " : s) + o;
}


static void ping_okInCleanUp() {


  if (ping_pauseAll || ping_anyActions)
    ping_impl(true);


}


// this syntax should be removed...
static Object getThreadLocal(Object o, String name) {
  ThreadLocal t =  (ThreadLocal) (getOpt(o, name));
  return t != null ? t.get() : null;
}

static <A> A getThreadLocal(ThreadLocal<A> tl) {
  return tl == null ? null : tl.get();
}

static <A> A getThreadLocal(ThreadLocal<A> tl, A defaultValue) {
  return or(getThreadLocal(tl), defaultValue);
}


static ThreadLocal<Object> print_byThread_dontCreate() {
  return print_byThread;
}


static boolean isFalse(Object o) {
  return eq(false, o);
}



static Map<Class, ArrayList<Method>> callF_cache = newDangerousWeakHashMap();



  static <A> A callF(F0<A> f) {
    return f == null ? null : f.get();
  }



  static <A, B> B callF(F1<A, B> f, A a) {
    return f == null ? null : f.get(a);
  }



  static <A> A callF(IF0<A> f) {
    return f == null ? null : f.get();
  }



  static <A, B> B callF(IF1<A, B> f, A a) {
    return f == null ? null : f.get(a);
  }


static <A, B> B callF(A a, IF1<A, B> f) {
  return f == null ? null : f.get(a);
}




  static <A, B, C> C callF(IF2<A, B, C> f, A a, B b) {
    return f == null ? null : f.get(a, b);
  }



  static <A> void callF(VF1<A> f, A a) {
    if (f != null) f.get(a);
  }


static <A> void callF(A a, IVF1<A> f) {
  if (f != null) f.get(a);
}

static <A> void callF(IVF1<A> f, A a) {
  if (f != null) f.get(a);
}


static Object callF(Runnable r) { { if (r != null) r.run(); } return null; }


static Object callF(Object f, Object... args) {
  
    
  return safeCallF(f, args);
}

static Object safeCallF(Object f, Object... args) {
  if (f instanceof Runnable) {
    ((Runnable) f).run();
    return null;
  }
  if (f == null) return null;
  
  Class c = f.getClass();
  ArrayList<Method> methods;
  synchronized(callF_cache) {
    methods = callF_cache.get(c);
    if (methods == null)
      methods = callF_makeCache(c);
  }
  
  int n = l(methods);
  if (n == 0) {
    
    
    if (f instanceof String)
      throw fail("Legacy call: " + f);
    
    throw fail("No get method in " + getClassName(c));
  }
  if (n == 1) return invokeMethod(methods.get(0), f, args);
  for (int i = 0; i < n; i++) {
    Method m = methods.get(i);
    if (call_checkArgs(m, args, false))
      return invokeMethod(m, f, args);
  }
  throw fail("No matching get method in " + getClassName(c));
}

// used internally
static ArrayList<Method> callF_makeCache(Class c) {
  ArrayList<Method> l = new ArrayList();
  Class _c = c;
  do {
    for (Method m : _c.getDeclaredMethods())
      if (m.getName().equals("get")) {
        makeAccessible(m);
        l.add(m);
      }
    if (!l.isEmpty()) break;
    _c = _c.getSuperclass();
  } while (_c != null);
  callF_cache.put(c, l);
  return l;
}





static String getStackTrace(Throwable throwable) {
  lastException(throwable);
  return getStackTrace_noRecord(throwable);
}

static String getStackTrace_noRecord(Throwable throwable) {
  StringWriter writer = new StringWriter();
  throwable.printStackTrace(new PrintWriter(writer));
  return hideCredentials(writer.toString());
}

static String getStackTrace() {
  return getStackTrace_noRecord(new Throwable());
}

static String getStackTrace(String msg) {
  return getStackTrace_noRecord(new Throwable(msg));
}


static String fixNewLines(String s) {
  int i = indexOf(s, '\r');
  if (i < 0) return s;
  int l = s.length();
  StringBuilder out = new StringBuilder(l);
  out.append(s, 0, i);
  for (; i < l; i++) {
    char c = s.charAt(i);
    if (c != '\r')
      out.append(c);
    else {
      out.append('\n');
      if (i+1 < l && s.charAt(i+1) == '\n') ++i;
    }
  }
  return out.toString();
}


static void print_append(Appendable buf, String s, int max) { try {
  synchronized(buf) {
    buf.append(s);
    if (buf instanceof StringBuffer)
      rotateStringBuffer(((StringBuffer) buf), max);
    else if (buf instanceof StringBuilder)
      rotateStringBuilder(((StringBuilder) buf), max);
  }
} catch (Exception __e) { throw rethrow(__e); } }


static void vmBus_send(String msg, Object... args) {
  Object arg = vmBus_wrapArgs(args);
  pcallFAll_minimalExceptionHandling(vm_busListeners_live(), msg, arg);
  pcallFAll_minimalExceptionHandling(vm_busListenersByMessage_live().get(msg), msg, arg);
}

static void vmBus_send(String msg) {
  vmBus_send(msg, (Object) null);
}


static Class mc() {
  return main.class;
}


static <A, B> Map<A, B> newWeakHashMap() {
  return _registerWeakMap(synchroMap(new WeakHashMap()));
}


static void newPing() {
  var tl = newPing_actionTL();
  Runnable action = tl == null ? null : tl.get();
  { if (action != null) action.run(); }
}


// TODO: test if android complains about this
static boolean isAWTThread() {
  if (isAndroid()) return false;
  if (isHeadless()) return false;
  return isAWTThread_awt();
}

static boolean isAWTThread_awt() {
  return SwingUtilities.isEventDispatchThread();
}


static boolean isTrue(Object o) {
  if (o instanceof Boolean)
    return ((Boolean) o).booleanValue();
  if (o == null) return false;
  if (o instanceof ThreadLocal) // TODO: remove this
    return isTrue(((ThreadLocal) o).get());
  throw fail(getClassName(o));
}

static boolean isTrue(Boolean b) {
  return b != null && b.booleanValue();
}


static void failIfUnlicensed() {
  assertTrue("license off", licensed());
}


static Thread currentThread() {
  return Thread.currentThread();
}


static RuntimeException fail() { throw new RuntimeException("fail"); }
static RuntimeException fail(Throwable e) { throw asRuntimeException(e); }
static RuntimeException fail(Object msg) { throw new RuntimeException(String.valueOf(msg)); }


static RuntimeException fail(Object... objects) { throw new Fail(objects); }


static RuntimeException fail(String msg) { throw new RuntimeException(msg == null ? "" : msg); }
static RuntimeException fail(String msg, Throwable innerException) { throw new RuntimeException(msg, innerException); }



static RuntimeException rethrow(Throwable t) {
  
  if (t instanceof Error)
    _handleError((Error) t);
  
  throw t instanceof RuntimeException ? (RuntimeException) t : new RuntimeException(t);
}

static RuntimeException rethrow(String msg, Throwable t) {
  throw new RuntimeException(msg, t);
}


static <A> int iteratorCount_int_close(Iterator<A> i) { try {
  int n = 0;
  if (i != null) while (i.hasNext()) { i.next(); ++n; }
  if (i instanceof AutoCloseable) ((AutoCloseable) i).close();
  return n;
} catch (Exception __e) { throw rethrow(__e); } }


static <A> boolean addToCollection(Collection<A> c, A a) {
  return c != null && c.add(a);
}


static <A, B> Pair<A, B> mapEntryToPair(Map.Entry<A, B> e) {
  return e == null ? null : pair(e.getKey(), e.getValue());
}


static <A, B> Set<Map.Entry<A,B>> entrySet(Map<A, B> map) {
  return _entrySet(map);
}


static <A, B> Pair<A, B> pair(A a, B b) {
  return new Pair(a, b);
}

static <A> Pair<A, A> pair(A a) {
  return new Pair(a, a);
}


static <A> A firstThat(Iterable<A> l, IF1<A, Boolean> pred) {
  for (A a : unnullForIteration(l))
    if (pred.get(a))
      return a;
  return null;
}

static <A> A firstThat(A[] l, IF1<A, Boolean> pred) {
  for (A a : unnullForIteration(l))
    if (pred.get(a))
      return a;
  return null;
}

static <A> A firstThat(IF1<A, Boolean> pred, Iterable<A> l) {
  return firstThat(l, pred);
}

static <A> A firstThat(IF1<A, Boolean> pred, A[] l) {
  return firstThat(l, pred);
}





static final Pt[] onePathDirections_directions = {
  pt(0, 0),
  pt(-1, -1),
  pt(0, -1),
  pt(1, -1),
  pt(1, 0),
  pt(1, 1),
  pt(0, 1),
  pt(-1, 1),
  pt(-1, 0)
};

static Pt[] onePathDirections() { return onePathDirections_directions; }


static Pt ptPlus(Pt a, Pt b) {
  return addPts(a, b);
}


static <A> List<A> nonNulls(Iterable<A> l) {
  return withoutNulls(l);
}

static <A> List<A> nonNulls(A[] l) {
  return withoutNulls(l);
}

static <A, B> Map<A, B> nonNulls(Map<A, B> map) {
  return withoutNulls(map);
}


static Steppable combineSteppables(Iterable<? extends Steppable> steppables) {
  return iteratorToSteppable(roundRobinCombinedIterator(map(__17 -> steppableToIterator(__17), steppables)));
}

static <A extends Steppable> Steppable combineSteppables(A... steppables) {
  return combineSteppables(asList(steppables));
}


// unclear semantics as to whether return null on null

static <A> ArrayList<A> asList(A[] a) {
  return a == null ? new ArrayList<A>() : new ArrayList<A>(Arrays.asList(a));
}

static ArrayList<Integer> asList(int[] a) {
  if (a == null) return null;
  ArrayList<Integer> l = emptyList(a.length);
  for (int i : a) l.add(i);
  return l;
}

static ArrayList<Long> asList(long[] a) {
  if (a == null) return null;
  ArrayList<Long> l = emptyList(a.length);
  for (long i : a) l.add(i);
  return l;
}

static ArrayList<Float> asList(float[] a) {
  if (a == null) return null;
  ArrayList<Float> l = emptyList(a.length);
  for (float i : a) l.add(i);
  return l;
}

static ArrayList<Double> asList(double[] a) {
  if (a == null) return null;
  ArrayList<Double> l = emptyList(a.length);
  for (double i : a) l.add(i);
  return l;
}

static ArrayList<Short> asList(short[] a) {
  if (a == null) return null;
  ArrayList<Short> l = emptyList(a.length);
  for (short i : a) l.add(i);
  return l;
}

static <A> ArrayList<A> asList(Iterator<A> it) {
  ArrayList l = new ArrayList();
  if (it != null)
    while (it.hasNext())
      l.add(it.next());
  return l;  
}

// disambiguation
static <A> ArrayList<A> asList(IterableIterator<A> s) {
  return asList((Iterator) s);
}

static <A> ArrayList<A> asList(Iterable<A> s) {
  if (s instanceof ArrayList) return (ArrayList) s;
  ArrayList l = new ArrayList();
  if (s != null)
    for (A a : s)
      l.add(a);
  return l;
}



static <A> ArrayList<A> asList(Enumeration<A> e) {
  ArrayList l = new ArrayList();
  if (e != null)
    while (e.hasMoreElements())
      l.add(e.nextElement());
  return l;
}




static <A> List<A> asList(Pair<A, A> p) {
  return p == null ? null : ll(p.a, p.b);
}



// TODO: JDK 17!! ?? No! Yes? Yes!!

static Object collectionMutex(List l) {
  return l;
}

static Object collectionMutex(Object o) {
  

  if (o instanceof List) return o;
  
  // TODO: actually use our own maps so we can get the mutex properly
  
  String c = className(o);
  
    
  
    
  
  return o;
}


static String renderVarsInMultipleLines(Object... params) {
  List<String> l = new ArrayList();
  int i = 0;
  String header = null;
  if (odd(l(params))) {
    header = strOrNull(first(params));
    addIfNempty(l, header);
    ++i;
  }
  for (; i+1 < l(params); i += 2)
    l.add(stringIf(nempty(header), "  ") + params[i] + "=" + params[i+1]);
  return lines_rtrim(l);
}


static <A, B> Collection<B> values(Map<A, B> map) {
  return map == null ? emptyList() : map.values();
}

// convenience shortcut for values_gen
static Collection values(Object map) {
  return values((Map) map);
}


static <A, B> Collection<B> values(MultiMap<A, B> mm) {
  return mm == null ? emptyList() : concatLists(values(mm.data));
}





static String str(Object o) {
  return o == null ? "null" : o.toString();
}

static String str(char[] c) {
  return new String(c);
}

static String str(char[] c, int offset, int count) {
  return new String(c, offset, count);
}


static <A> List<A> reverseList(List<A> l) {
  Collections.reverse(l);
  return l;
}


// get purpose 1: access a list/array/map (safer version of x.get(y))

static <A> A get(List<A> l, int idx) {
  return l != null && idx >= 0 && idx < l(l) ? l.get(idx) : null;
}

// seems to conflict with other signatures
/*static <A, B> B get(Map<A, B> map, A key) {
  ret map != null ? map.get(key) : null;
}*/

static <A> A get(A[] l, int idx) {
  return idx >= 0 && idx < l(l) ? l[idx] : null;
}

// default to false
static boolean get(boolean[] l, int idx) {
  return idx >= 0 && idx < l(l) ? l[idx] : false;
}

// get purpose 2: access a field by reflection or a map

static Object get(Object o, String field) {
  try {
    if (o == null) return null;
    if (o instanceof Class) return get((Class) o, field);
    
    if (o instanceof Map)
      return ((Map) o).get(field);
      
    Field f = getOpt_findField(o.getClass(), field);
    if (f != null) {
      makeAccessible(f);
      return f.get(o);
    }
      
    
      if (o instanceof DynamicObject)
        return getOptDynOnly(((DynamicObject) o), field);
    
  } catch (Exception e) {
    throw asRuntimeException(e);
  }
  throw new RuntimeException("Field '" + field + "' not found in " + o.getClass().getName());
}

static Object get_raw(String field, Object o) {
  return get_raw(o, field);
}

static Object get_raw(Object o, String field) { try {
  if (o == null) return null;
  Field f = get_findField(o.getClass(), field);
  makeAccessible(f);
  return f.get(o);
} catch (Exception __e) { throw rethrow(__e); } }

static Object get(Class c, String field) {
  try {
    Field f = get_findStaticField(c, field);
    makeAccessible(f);
    return f.get(null);
  } catch (Exception e) {
    throw new RuntimeException(e);
  }
}

static Field get_findStaticField(Class<?> c, String field) {
  Class _c = c;
  do {
    for (Field f : _c.getDeclaredFields())
      if (f.getName().equals(field) && (f.getModifiers() & java.lang.reflect.Modifier.STATIC) != 0)
        return f;
    _c = _c.getSuperclass();
  } while (_c != null);
  throw new RuntimeException("Static field '" + field + "' not found in " + c.getName());
}

static Field get_findField(Class<?> c, String field) {
  Class _c = c;
  do {
    for (Field f : _c.getDeclaredFields())
      if (f.getName().equals(field))
        return f;
    _c = _c.getSuperclass();
  } while (_c != null);
  throw new RuntimeException("Field '" + field + "' not found in " + c.getName());
}

static Object get(String field, Object o) {
  return get(o, field);
}

static boolean get(BitSet bs, int idx) {
  return bs != null && bs.get(idx);
}


static <A> Iterator<A> iterator(Iterable<A> c) {
  return c == null ? emptyIterator() : c.iterator();
}


static char charAt(String s, int i) {
  return s != null && i >= 0 && i < s.length() ? s.charAt(i) : '\0';
}


static ThreadLocal<Boolean> assertVerbose_value = new ThreadLocal();

static void assertVerbose(boolean b) {
  assertVerbose_value.set(b);
}

static boolean assertVerbose() { return isTrue(assertVerbose_value.get()); }


static <A> A assertEqualsVerbose(Object x, A y) {
  assertEqualsVerbose((String) null, x, y);
  return y;
}

// x = expected, y = actual
static <A> A assertEqualsVerbose(String msg, Object x, A y) {
  if (!eq(x, y)) {
    

    throw fail((nempty(msg) ? msg + ": " : "") + "expected: "+ x + ", got: " + y);
  } else
    print("OK" + (empty(msg) ? "" : " " + msg) + ": " + /*sfu*/(x));
  return y;
}




static String nullIfEmpty(String s) {
  return isEmpty(s) ? null : s;
}

static <A, B> Map<A, B> nullIfEmpty(Map<A, B> map) {
  return isEmpty(map) ? null : map;
}

static <A> List<A> nullIfEmpty(List<A> l) {
  return isEmpty(l) ? null : l;
}


static <A extends Container> A addComponents(A c, Collection<? extends Component> components) {
  if (nempty(components)) { swing(() -> { 
    for (Component comp : components)
      if (comp != null)
        c.add(comp);
    revalidate(c);
  }); }
  return c;
}

static <A extends Container> A addComponents(A c, Component... components) {
  return addComponents(c, asList(components));
}


static void assertTrue(Object o) {
  if (!(eq(o, true) /*|| isTrue(pcallF(o))*/))
    throw fail(str(o));
}
  
static boolean assertTrue(String msg, boolean b) {
  if (!b)
    throw fail(msg);
  return b;
}

static boolean assertTrue(boolean b) {
  if (!b)
    throw fail("oops");
  return b;
}




static ThreadLocal<Object> print_byThread() {
  synchronized(print_byThread_lock) {
    if (print_byThread == null)
      print_byThread = new ThreadLocal();
  }
  return print_byThread;
}


// f can return false to suppress regular printing
// call print_raw within f to actually print something
static AutoCloseable tempInterceptPrint(F1<String, Boolean> f) {
  return tempSetThreadLocal(print_byThread(), f);
}


static String[] dropFirst(int n, String[] a) {
  return drop(n, a);
}

static String[] dropFirst(String[] a) {
  return drop(1, a);
}

static Object[] dropFirst(Object[] a) {
  return drop(1, a);
}

static <A> List<A> dropFirst(List<A> l) {
  return dropFirst(1, l);
}

static <A> List<A> dropFirst(int n, Iterable<A> i) { return dropFirst(n, toList(i)); }
static <A> List<A> dropFirst(Iterable<A> i) { return dropFirst(toList(i)); }

static <A> List<A> dropFirst(int n, List<A> l) {
  return n <= 0 ? l : new ArrayList(l.subList(Math.min(n, l.size()), l.size()));
}

static <A> List<A> dropFirst(List<A> l, int n) {
  return dropFirst(n, l);
}

static String dropFirst(int n, String s) { return substring(s, n); }
static String dropFirst(String s, int n) { return substring(s, n); }
static String dropFirst(String s) { return substring(s, 1); }




static int indexOfNonDigit(String s) {
  int n = l(s);
  for (int i = 0; i < n; i++)
    if (!isDigit(s.charAt(i)))
      return i;
  return -1;
}


static String shortenClassName(String name) {
  if (name == null) return null;
  int i = lastIndexOf(name, "$");
  if (i < 0) i = lastIndexOf(name, ".");
  return i < 0 ? name : substring(name, i+1);
}


static String getType(Object o) {
  return getClassName(o);
}


static long getFileSize(String path) {
  return path == null ? 0 : new File(path).length();
}

static long getFileSize(File f) {
  return f == null ? 0 : f.length();
}


static <A> List<A> cloneSubList(List<A> l, int startIndex, int endIndex) {
  return newSubList(l, startIndex, endIndex);
}

static <A> List<A> cloneSubList(List<A> l, int startIndex) {
  return newSubList(l, startIndex);
}


static void removeSubList(List l, int from, int to) {
  if (l != null) subList(l, from, to).clear();
}

static void removeSubList(List l, int from) {
  if (l != null) subList(l, from).clear();
}


static boolean endsWithLetterOrDigit(String s) {
  return s != null && s.length() > 0 && Character.isLetterOrDigit(s.charAt(s.length()-1));
}


static Object getOpt(Object o, String field) {
  return getOpt_cached(o, field);
}

static Object getOpt(String field, Object o) {
  return getOpt_cached(o, field);
}

static Object getOpt_raw(Object o, String field) { try {
  Field f = getOpt_findField(o.getClass(), field);
  if (f == null) return null;
  makeAccessible(f);
  return f.get(o);
} catch (Exception __e) { throw rethrow(__e); } }

// access of static fields is not yet optimized
static Object getOpt(Class c, String field) { try {
  if (c == null) return null;
  Field f = getOpt_findStaticField(c, field);
  if (f == null) return null;
  makeAccessible(f);
  return f.get(null);
} catch (Exception __e) { throw rethrow(__e); } }

static Field getOpt_findStaticField(Class<?> c, String field) {
  Class _c = c;
  do {
    for (Field f : _c.getDeclaredFields())
      if (f.getName().equals(field) && (f.getModifiers() & java.lang.reflect.Modifier.STATIC) != 0)
        return f;
    _c = _c.getSuperclass();
  } while (_c != null);
  return null;
}



static <A> A or(A a, A b) {
  return a != null ? a : b;
}


static <A, B> Map<A, B> newDangerousWeakHashMap() {
  return _registerDangerousWeakMap(synchroMap(new WeakHashMap()));
}

// initFunction: voidfunc(Map) - is called initially, and after clearing the map
static <A, B> Map<A, B> newDangerousWeakHashMap(Object initFunction) {
  return _registerDangerousWeakMap(synchroMap(new WeakHashMap()), initFunction);
}


static String getClassName(Object o) {
  return o == null ? "null" : o instanceof Class ? ((Class) o).getName() : o.getClass().getName();
}


static Object invokeMethod(Method m, Object o, Object... args) { try {
  try {
    return m.invoke(o, args);
  } catch (InvocationTargetException e) {
    throw rethrow(getExceptionCause(e));
  } catch (IllegalArgumentException e) {
    throw new IllegalArgumentException(e.getMessage() + " - was calling: " + m + ", args: " + joinWithSpace(classNames(args)));
  }
} catch (Exception __e) { throw rethrow(__e); } }


static boolean call_checkArgs(Method m, Object[] args, boolean debug) {
  Class<?>[] types = m.getParameterTypes();
  if (types.length != l(args)) {
    if (debug)
      print("Bad parameter length: " + args.length + " vs " + types.length);
    return false;
  }
  for (int i = 0; i < types.length; i++) {
    Object arg = args[i];
    if (!(arg == null ? !types[i].isPrimitive()
      : isInstanceX(types[i], arg))) {
      if (debug)
        print("Bad parameter " + i + ": " + arg + " vs " + types[i]);
      return false;
    }
  }
  return true;
}


static Field makeAccessible(Field f) {
  try {
    f.setAccessible(true);
  } catch (Throwable e) {
    // Note: The error reporting only works with Java VM option --illegal-access=deny
    
    vmBus_send("makeAccessible_error", e, f);
    
  }
  return f;
}

static Method makeAccessible(Method m) {
  try {
    m.setAccessible(true);
  } catch (Throwable e) {
    
    vmBus_send("makeAccessible_error", e, m);
    
  }
  return m;
}

static Constructor makeAccessible(Constructor c) {
  try {
    c.setAccessible(true);
  } catch (Throwable e) {
    
    vmBus_send("makeAccessible_error", e, c);
    
  }
  return c;
}


// PersistableThrowable doesn't hold GC-disturbing class references in backtrace
static volatile PersistableThrowable lastException_lastException;

static PersistableThrowable lastException() {
  return lastException_lastException;
}

static void lastException(Throwable e) {
  lastException_lastException = persistableThrowable(e);
}


static String hideCredentials(URL url) { return url == null ? null : hideCredentials(str(url)); }

static String hideCredentials(String url) {
  try {
    if (startsWithOneOf(url, "http://", "https://") && isAGIBlueDomain(hostNameFromURL(url))) return url;
  } catch (Throwable e) {
    print("HideCredentials", e);
  }
  return url.replaceAll("([&?])(_pass|key|cookie)=[^&\\s\"]*", "$1$2=<hidden>");
}

static String hideCredentials(Object o) {
  return hideCredentials(str(o));
}


static <A> int indexOf(List<A> l, A a, int startIndex) {
  if (l == null) return -1;
  int n = l(l);
  for (int i = startIndex; i < n; i++)
    if (eq(l.get(i), a))
      return i;
  return -1;
}

static <A> int indexOf(List<A> l, int startIndex, A a) {
  return indexOf(l, a, startIndex);
}

static <A> int indexOf(List<A> l, A a) {
  if (l == null) return -1;
  return l.indexOf(a);
}

static int indexOf(String a, String b) {
  return a == null || b == null ? -1 : a.indexOf(b);
}

static int indexOf(String a, String b, int i) {
  return a == null || b == null ? -1 : a.indexOf(b, i);
}

static int indexOf(String a, char b) {
  return a == null ? -1 : a.indexOf(b);
}

static int indexOf(String a, int i, char b) {
  return indexOf(a, b, i);
}

static int indexOf(String a, char b, int i) {
  return a == null ? -1 : a.indexOf(b, i);
}

static int indexOf(String a, int i, String b) {
  return a == null || b == null ? -1 : a.indexOf(b, i);
}

static <A> int indexOf(A[] x, A a) {
  int n = l(x);
  for (int i = 0; i < n; i++)
    if (eq(x[i], a))
      return i;
  return -1;
}

static <A> int indexOf(Iterable<A> l, A a) {
  if (l == null) return -1;
  int i = 0;
  for (A x : l) {
    if (eq(x, a))
      return i;
    i++;
  }
  return -1;
}



static void rotateStringBuffer(StringBuffer buf, int max) { try {
  if (buf == null) return;
  synchronized(buf) {
    if (buf.length() <= max) return;
    
    try {
      int newLength = max/2;
      int ofs = buf.length()-newLength;
      String newString = buf.substring(ofs);
      buf.setLength(0);
      buf.append("[...] ").append(newString);
    } catch (Exception e) {
      buf.setLength(0);
    }
    buf.trimToSize();
  }
} catch (Exception __e) { throw rethrow(__e); } }


static void rotateStringBuilder(StringBuilder buf, int max) { try {
  if (buf == null) return;
  synchronized(buf) {
    if (buf.length() <= max) return;
    
    try {
      int newLength = max/2;
      int ofs = buf.length()-newLength;
      String newString = buf.substring(ofs);
      buf.setLength(0);
      buf.append("[...] ").append(newString);
    } catch (Exception e) {
      buf.setLength(0);
    }
    buf.trimToSize();
  }
} catch (Exception __e) { throw rethrow(__e); } }


static Object vmBus_wrapArgs(Object... args) {
  return empty(args) ? null
    : l(args) == 1 ? args[0]
    : args;
}


static void pcallFAll_minimalExceptionHandling(Collection l, Object... args) {
  if (l != null) for  (Object f : cloneList(l)) { ping(); pcallF_minimalExceptionHandling(f, args); }
}

static void pcallFAll_minimalExceptionHandling(Iterator it, Object... args) {
  while  (it.hasNext()) { ping(); pcallF_minimalExceptionHandling(it.next(), args); }
}


static Set vm_busListeners_live_cache;
static Set vm_busListeners_live() { if (vm_busListeners_live_cache == null) vm_busListeners_live_cache = vm_busListeners_live_load(); return vm_busListeners_live_cache;}

static Set vm_busListeners_live_load() {
  return vm_generalIdentityHashSet("busListeners");
}


static Map<String, Set> vm_busListenersByMessage_live_cache;
static Map<String, Set> vm_busListenersByMessage_live() { if (vm_busListenersByMessage_live_cache == null) vm_busListenersByMessage_live_cache = vm_busListenersByMessage_live_load(); return vm_busListenersByMessage_live_cache;}

static Map<String, Set> vm_busListenersByMessage_live_load() {
  return vm_generalHashMap("busListenersByMessage");
}


static List _registerWeakMap_preList;

static <A> A _registerWeakMap(A map) {
  if (javax() == null) {
    // We're in class init
    if (_registerWeakMap_preList == null) _registerWeakMap_preList = synchroList();
    _registerWeakMap_preList.add(map);
    return map;
  }
  
  try {
    call(javax(), "_registerWeakMap", map);
  } catch (Throwable e) {
    printException(e);
    print("Upgrade JavaX!!");
  }
  return map;
}

static void _onLoad_registerWeakMap() {
  assertNotNull(javax());
  if (_registerWeakMap_preList == null) return;
  for (Object o : _registerWeakMap_preList)
    _registerWeakMap(o);
  _registerWeakMap_preList = null;
}


static Map synchroMap() {
  return synchroHashMap();
}

static <A, B> Map<A, B> synchroMap(Map<A, B> map) {
  
  
    return Collections.synchronizedMap(map);
  
}


static x30_pkg.x30_util.BetterThreadLocal<Runnable> newPing_actionTL;

static x30_pkg.x30_util.BetterThreadLocal<Runnable> newPing_actionTL() {
  if (newPing_actionTL == null)
    newPing_actionTL = vm_generalMap_getOrCreate("newPing_actionTL",
      () -> {
        Runnable value =  (Runnable) (callF_gen(vm_generalMap_get("newPing_valueForNewThread")));
        var tl = new x30_pkg.x30_util.BetterThreadLocal<Runnable>();
        tl.set(value);
        return tl;
      });
  return newPing_actionTL;
}



static int isAndroid_flag;

static boolean isAndroid() {
  if (isAndroid_flag == 0)
    isAndroid_flag = System.getProperty("java.vendor").toLowerCase().indexOf("android") >= 0 ? 1 : -1;
  return isAndroid_flag > 0;
}



static Boolean isHeadless_cache;

static boolean isHeadless() {
  if (isHeadless_cache != null) return isHeadless_cache;
  if (isAndroid()) return isHeadless_cache = true;
  if (GraphicsEnvironment.isHeadless()) return isHeadless_cache = true;
  
  // Also check if AWT actually works.
  // If DISPLAY variable is set but no X server up, this will notice.
  
  try {
    SwingUtilities.isEventDispatchThread();
    return isHeadless_cache = false;
  } catch (Throwable e) { return isHeadless_cache = true; }
}


static volatile boolean licensed_yes = true;

static boolean licensed() {
  if (!licensed_yes) return false;
  ping_okInCleanUp();
  return true;
}

static void licensed_off() {
  licensed_yes = false;
}


static RuntimeException asRuntimeException(Throwable t) {
  
  if (t instanceof Error)
    _handleError((Error) t);
  
  return t instanceof RuntimeException ? (RuntimeException) t : new RuntimeException(t);
}


static void _handleError(Error e) {
  //call(javax(), '_handleError, e);
}


static <A, B> Set<Map.Entry<A,B>> _entrySet(Map<A, B> map) {
  return map == null ? Collections.EMPTY_SET : map.entrySet();
}


static String unnullForIteration(String s) {
  return s == null ? "" : s;
}

static <A> Collection<A> unnullForIteration(Collection<A> l) {
  return l == null ? immutableEmptyList() : l;
}

static <A> List<A> unnullForIteration(List<A> l) { return l == null ? immutableEmptyList() : l; }
static int[] unnullForIteration(int[] l) { return l == null ? emptyIntArray() : l; }
static char[] unnullForIteration(char[] l) { return l == null ? emptyCharArray() : l; }
static double[] unnullForIteration(double[] l) { return l == null ? emptyDoubleArray() : l; }
static short[] unnullForIteration(short[] l) { return l == null ? emptyShortArray() : l; }

static <A, B> Map<A, B> unnullForIteration(Map<A, B> l) {
  return l == null ? immutableEmptyMap() : l;
}

static <A> Iterable<A> unnullForIteration(Iterable<A> i) {
  return i == null ? immutableEmptyList() : i;
}

static <A> A[] unnullForIteration(A[] a) {
  return a == null ? (A[]) emptyObjectArray() : a;
}

static BitSet unnullForIteration(BitSet b) {
  return b == null ? new BitSet() : b;
}


static Pt unnullForIteration(Pt p) {
  return p == null ? new Pt() : p;
}


//ifclass Symbol

static Symbol unnullForIteration(Symbol s) {
  return s == null ? emptySymbol() : s;
}
//endif



static <A, B> Pair<A, B> unnullForIteration(Pair<A, B> p) {
  return p != null ? p : new Pair(null, null);
}


static long unnullForIteration(Long l) { return l == null ? 0L : l; }


static Pt pt(int x, int y) {
  return new Pt(x, y);
}

static Pt pt(int x) {
  return new Pt(x, x);
}


static Pt addPts(Pt a, Pt b) {
  return a == null ? b : b == null ? a : new Pt(a.x+b.x, a.y+b.y);
}


static <A> List<A> withoutNulls(Iterable<A> l) {
  if (l instanceof List)
    if (!containsNulls((List) l)) return ((List) l);
  List<A> l2 = new ArrayList();
  for (A a : l)
    if (a != null)
      l2.add(a);
  return l2;
}

static <A, B> Map<A, B> withoutNulls(Map<A, B> map) {
  Map<A, B> map2 = similarEmptyMap(map);
  for (A a : keys(map))
    if (a != null) {
      B b = map.get(a);
      if (b != null)
        map2.put(a, b);
    }
  return map2;
}

static <A> List<A> withoutNulls(A[] l) {
  List<A> l2 = new ArrayList();
  if (l != null) for (A a : l)
    if (a != null)
      l2.add(a);
  return l2;
}


static Steppable iteratorToSteppable(Iterator it) {
  return it == null ? null : new Steppable() {
    public boolean step() {
      if (!it.hasNext()) return false;
      it.next();
      return true;
    }
  };
}


static <A> IterableIterator<A> roundRobinCombinedIterator(Iterator<A>... iterators) {
  return roundRobinCombinedIterator(wrapAsList(iterators));
}

static <A> IterableIterator<A> roundRobinCombinedIterator(Collection<? extends Iterator<A>> iterators) {
  if (empty(iterators)) return emptyItIt();
  class Robin implements IF0 {
    List<? extends Iterator<A>> activeIterators = cloneList(iterators);
    int i;
    
    public Object get() {
      while (licensed()) {
        Iterator<A> it = activeIterators.get(i);
        if (!it.hasNext()) { 
          activeIterators.remove(i);
          if (empty(activeIterators)) break;
          i %= l(activeIterators);
        } else {
          i = (i+1) % l(activeIterators);
          return it.next();
        }
      }
      return endMarker();
    }
  }
  
  return iff(new Robin());
}



static List map(Iterable l, Object f) { return map(f, l); }

static List map(Object f, Iterable l) {
  List x = emptyList(l);
  if (l != null) for  (Object o : l)
    { ping(); x.add(callF(f, o)); }
  return x;
}

// map: func(key, value) -> list element
static List map(Map map, Object f) {
  List x = new ArrayList();
  if (map != null) for  (Object _e : map.entrySet()) { ping(); 
    Map.Entry e = (Map.Entry) _e;
    x.add(callF(f, e.getKey(), e.getValue()));
  }
  return x;
}

static List map(Object f, Object[] l) { return map(f, asList(l)); }
static List map(Object[] l, Object f) { return map(f, l); }

static List map(Object f, Map map) {
  return map(map, f);
}




  static <A, B> List<B> map(Iterable<A> l, F1<A, B> f) { return map(f, l); }

  static <A, B> List<B> map(F1<A, B> f, Iterable<A> l) {
    List x = emptyList(l);
    if (l != null) for  (A o : l)
      { ping(); x.add(callF(f, o)); }
    return x;
  }


static <A, B> List<B> map(IF1<A, B> f, Iterable<A> l) { return map(l, f); }
static <A, B> List<B> map(Iterable<A> l, IF1<A, B> f) {
  List x = emptyList(l);
  if (l != null) for  (A o : l)
    { ping(); x.add(f.get(o)); }
  return x;
}
  
static <A, B> List<B> map(IF1<A, B> f, A[] l) { return map(l, f); }
static <A, B> List<B> map(A[] l, IF1<A, B> f) {
  List x = emptyList(l);
  if (l != null) for  (A o : l)
    { ping(); x.add(f.get(o)); }
  return x;
}
  
static <A, B, C> List<C> map(Map<A, B> map, IF2<A, B, C> f) {
  List x = new ArrayList();
  if (map != null) for  (Map.Entry<A, B> e : map.entrySet()) { ping(); 
    x.add(f.get(e.getKey(), e.getValue()));
  }
  return x;
}

// new magic alias for mapLL - does it conflict?

static <A, B> List<A> map(IF1<A, B> f, A data1, A... moreData) {
  List x = emptyList(l(moreData)+1);
  x.add(f.get(data1));
  if (moreData != null) for  (A o : moreData)
    { ping(); x.add(f.get(o)); }
  return x;
}


static IterableIterator<Object> steppableToIterator(Steppable s) {
  return s == null ? emptyItIt() : iff(() -> s.step() ? null : endMarker());
}


static ArrayList emptyList() {
  return new ArrayList();
  //ret Collections.emptyList();
}

static ArrayList emptyList(int capacity) {
  return new ArrayList(max(0, capacity));
}

// Try to match capacity
static ArrayList emptyList(Iterable l) {
  return l instanceof Collection ? emptyList(((Collection) l).size()) : emptyList();
}

static ArrayList emptyList(Object[] l) {
  return emptyList(l(l));
}

// get correct type at once
static <A> ArrayList<A> emptyList(Class<A> c) {
  return new ArrayList();
}


static <A> List<A> ll(A... a) {
  ArrayList l = new ArrayList(a.length);
  if (a != null) for (A x : a) l.add(x);
  return l;
}


static String className(Object o) {
  return getClassName(o);
}


static boolean odd(int i) {
  return (i & 1) != 0;
}

static boolean odd(long i) {
  return (i & 1) != 0;
}

static boolean odd(BigInteger i) { return odd(toInt(i)); }


static String strOrNull(Object o) {
  return o == null ? null : str(o);
}


static void addIfNempty(Collection<String> l, String s) {
  if (nempty(s)) l.add(s);
}

static void addIfNempty(Collection l, Map m) {
  if (nempty(m)) l.add(m);
}

static void addIfNempty(Collection l, Collection c) {
  if (nempty(c)) l.add(c);
}


static String stringIf(boolean b, String s) {
  return stringIfTrue(b, s);
}

static String stringIf(String s, boolean b) {
  return stringIf(b, s);
}


static String lines_rtrim(Collection lines) {
  return rtrim_fromLines(lines);
}


static Field getOpt_findField(Class<?> c, String field) {
  Class _c = c;
  do {
    for (Field f : _c.getDeclaredFields())
      if (f.getName().equals(field))
        return f;
    _c = _c.getSuperclass();
  } while (_c != null);
  return null;
}


static Object getOptDynOnly(DynamicObject o, String field) {
  if (o == null || o.fieldValues == null) return null;
  return o.fieldValues.get(field);
}


static Iterator emptyIterator() {
  return Collections.emptyIterator();
}


static String appendColonIfNempty(String s) {
  return empty(s) ? "" : s + ": ";
}


static boolean isEmpty(Collection c) {
  return c == null || c.isEmpty();
}

static boolean isEmpty(CharSequence s) {
  return s == null || s.length() == 0;
}

static boolean isEmpty(Object[] a) { return a == null || a.length == 0; }
static boolean isEmpty(byte[] a) { return a == null || a.length == 0; }

static boolean isEmpty(Map map) {
  return map == null || map.isEmpty();
}




static boolean isEmpty(AppendableChain c) { return c == null; }



static Object swing(Object f) {
  return swingAndWait(f);
}

static void swing(Runnable f) {
  swingAndWait(f);
}

static <A> A swing(F0<A> f) {
  return (A) swingAndWait(f);
}

static <A> A swing(IF0<A> f) {
  return (A) swingAndWait(f);
}


static <A extends Component> A revalidate(final A c) {
  if (c == null || !c.isShowing()) return c;
  { swing(() -> { 
    // magic combo to actually relayout and repaint
    c.revalidate();
    c.repaint();
  }); }
  return c;
}

static void revalidate(JFrame f) { revalidate((Component) f); }
static void revalidate(JInternalFrame f) { revalidate((Component) f); }




static <A> AutoCloseable tempSetThreadLocal(final ThreadLocal<A> tl, A a) {
  if (tl == null) return null;
  final A prev = setThreadLocal(tl, a);
  return new AutoCloseable() { public String toString() { return "tl.set(prev);"; } public void close() throws Exception { tl.set(prev); }};
}


static String[] drop(int n, String[] a) {
  n = Math.min(n, a.length);
  String[] b = new String[a.length-n];
  System.arraycopy(a, n, b, 0, b.length);
  return b;
}

static Object[] drop(int n, Object[] a) {
  n = Math.min(n, a.length);
  Object[] b = new Object[a.length-n];
  System.arraycopy(a, n, b, 0, b.length);
  return b;
}


static <A> ArrayList<A> toList(A[] a) { return asList(a); }
static ArrayList<Integer> toList(int[] a) { return asList(a); }
static <A> ArrayList<A> toList(Set<A> s) { return asList(s); }
static <A> ArrayList<A> toList(Iterable<A> s) { return asList(s); }


static String substring(String s, int x) {
  return substring(s, x, strL(s));
}

static String substring(String s, int x, int y) {
  if (s == null) return null;
  if (x < 0) x = 0;
  int n = s.length();
  if (y < x) y = x;
  if (y > n) y = n;
  if (x >= y) return "";
  return s.substring(x, y);
}



// convenience method for quickly dropping a prefix
static String substring(String s, CharSequence l) {
  return substring(s, lCharSequence(l));
}


static boolean isDigit(char c) {
  return Character.isDigit(c);
}


static int lastIndexOf(String a, String b) {
  return a == null || b == null ? -1 : a.lastIndexOf(b);
}

static int lastIndexOf(String a, char b) {
  return a == null ? -1 : a.lastIndexOf(b);
}

// starts searching from i-1
static <A> int lastIndexOf(List<A> l, int i, A a) {
  if (l == null) return -1;
  for (i = min(l(l), i)-1; i >= 0; i--)
    if (eq(l.get(i), a))
      return i;
  return -1;
}

static <A> int lastIndexOf(List<A> l, A a) {
  if (l == null) return -1;
  for (int i = l(l)-1; i >= 0; i--)
    if (eq(l.get(i), a))
      return i;
  return -1;
}


static <A> List<A> newSubList(List<A> l, int startIndex, int endIndex) {
  return cloneList(subList(l, startIndex, endIndex));
}

static <A> List<A> newSubList(List<A> l, int startIndex) {
  return cloneList(subList(l, startIndex));
}


static <A> List<A> subList(List<A> l, int startIndex) {
  return subList(l, startIndex, l(l));
}

static <A> List<A> subList(int startIndex, List<A> l) {
  return subList(l, startIndex);
}

static <A> List<A> subList(int startIndex, int endIndex, List<A> l) {
  return subList(l, startIndex, endIndex);
}

static <A> List<A> subList(List<A> l, int startIndex, int endIndex) {
  if (l == null) return null;
  int n = l(l);
  startIndex = Math.max(0, startIndex);
  endIndex = Math.min(n, endIndex);
  if (startIndex > endIndex) return ll();
  if (startIndex == 0 && endIndex == n) return l;
  
  
    return l.subList(startIndex, endIndex);
  
}




//static final Map<Class, HashMap<S, Field>> getOpt_cache = newDangerousWeakHashMap(f getOpt_special_init);

static class getOpt_Map extends WeakHashMap {
  getOpt_Map() {
    if (getOpt_special == null) getOpt_special = new HashMap();
    clear();
  }
  
  public void clear() {
    super.clear();
    //print("getOpt clear");
    put(Class.class, getOpt_special);
    put(String.class, getOpt_special);
  }
}

static final Map<Class, HashMap<String, Field>> getOpt_cache = _registerDangerousWeakMap(synchroMap(new getOpt_Map()));
//static final Map<Class, HashMap<S, Field>> getOpt_cache = _registerWeakMap(synchroMap(new getOpt_Map));
static HashMap getOpt_special; // just a marker

/*static void getOpt_special_init(Map map) {
  map.put(Class.class, getOpt_special);
  map.put(S.class, getOpt_special);
}*/

static Map<String, Field> getOpt_getFieldMap(Object o) {
  Class c = _getClass(o);
  HashMap<String, Field> map = getOpt_cache.get(c);
  if (map == null)
    map = getOpt_makeCache(c);
  return map;
}

static Object getOpt_cached(Object o, String field) { try {
  if (o == null) return null;

  Map<String, Field> map = getOpt_getFieldMap(o);

  if (map == getOpt_special) {
    if (o instanceof Class)
      return getOpt((Class) o, field);
    /*if (o instanceof S)
      ret getOpt(getBot((S) o), field);*/
    if (o instanceof Map)
      return ((Map) o).get(field);
  }
    
  Field f = map.get(field);
  if (f != null) return f.get(o);
  
    if (o instanceof DynamicObject)
      return syncMapGet2(((DynamicObject) o).fieldValues, field);
  
  return null;
} catch (Exception __e) { throw rethrow(__e); } }

// used internally - we are in synchronized block
static HashMap<String, Field> getOpt_makeCache(Class c) {
  HashMap<String, Field> map;
  if (isSubtypeOf(c, Map.class))
    map = getOpt_special;
  else {
    map = new HashMap();
    if (!reflection_classesNotToScan().contains(c.getName())) {
      Class _c = c;
      do {
        for (Field f : _c.getDeclaredFields()) {
          makeAccessible(f);
          String name = f.getName();
          if (!map.containsKey(name))
            map.put(name, f);
        }
        _c = _c.getSuperclass();
      } while (_c != null);
    }
  }
  if (getOpt_cache != null) getOpt_cache.put(c, map);
  return map;
}


static List<Pair> _registerDangerousWeakMap_preList;

static <A> A _registerDangerousWeakMap(A map) {
  return _registerDangerousWeakMap(map, null);
}

static <A> A _registerDangerousWeakMap(A map, Object init) {
  
  callF(init, map);
  
  if (init instanceof String) {
    final String f =  (String) init;
    init = new VF1<Map>() { public void get(Map map) { try {  callMC(f, map) ; } catch (Exception __e) { throw rethrow(__e); } }
  public String toString() { return "callMC(f, map)"; }};
  }
    
  if (javax() == null) {
    // We're in class init
    if (_registerDangerousWeakMap_preList == null) _registerDangerousWeakMap_preList = synchroList();
    _registerDangerousWeakMap_preList.add(pair(map, init));
    return map;
  }
  
  call(javax(), "_registerDangerousWeakMap", map, init);
  
  return map;
}

static void _onLoad_registerDangerousWeakMap() {
  
  assertNotNull(javax());
  if (_registerDangerousWeakMap_preList == null) return;
  for (Pair p : _registerDangerousWeakMap_preList)
    _registerDangerousWeakMap(p.a, p.b);
  _registerDangerousWeakMap_preList = null;
  
}


static Throwable getExceptionCause(Throwable e) {
  Throwable c = e.getCause();
  return c != null ? c : e;
}


static String joinWithSpace(Iterable c) {
  return join(" ", c);
}

static String joinWithSpace(String... c) {
  return join(" ", c);
}



static List<String> classNames(Collection l) {
  return getClassNames(l);
}

static List<String> classNames(Object[] l) {
  return getClassNames(asList(l));
}


static boolean isInstanceX(Class type, Object arg) {
  if (type == boolean.class) return arg instanceof Boolean;
  if (type == int.class) return arg instanceof Integer;
  if (type == long.class) return arg instanceof Long;
  if (type == float.class) return arg instanceof Float;
  if (type == short.class) return arg instanceof Short;
  if (type == char.class) return arg instanceof Character;
  if (type == byte.class) return arg instanceof Byte;
  if (type == double.class) return arg instanceof Double;
  return type.isInstance(arg);
}


static PersistableThrowable persistableThrowable(Throwable e) {
  return e == null ? null : new PersistableThrowable(e);
}


static boolean startsWithOneOf(String s, String... l) {
  for (String x : l) if (startsWith(s, x)) return true; return false;
}

static boolean startsWithOneOf(String s, Matches m, String... l) {
  for (String x : l) if (startsWith(s, x, m)) return true; return false;
}


static boolean isAGIBlueDomain(String domain) {
  return domainIsUnder(domain, theAGIBlueDomain());
}


static String hostNameFromURL(String url) { try {
  return empty(url) ? null : new URL(url).getHost();
} catch (Exception __e) { throw rethrow(__e); } }


static Object pcallF_minimalExceptionHandling(Object f, Object... args) {
  try {
    return callFunction(f, args);
  } catch (Throwable e) {
    System.out.println(getStackTrace(e));
    _storeException(e);
  }
  return null;
}


static Set vm_generalIdentityHashSet(Object name) {
  synchronized(vm_generalMap()) {
    Set set =  (Set) (vm_generalMap_get(name));
    if (set == null)
      vm_generalMap_put(name, set = syncIdentityHashSet());
    return set;
  }
}



static Map vm_generalHashMap(Object name) {
  synchronized(vm_generalMap()) {
    Map m =  (Map) (vm_generalMap_get(name));
    if (m == null)
      vm_generalMap_put(name, m = syncHashMap());
    return m;
  }
}



static Class javax() {
  return getJavaX();
}


static <A> List<A> synchroList() {
  return synchroList(new ArrayList<A>());
}

static <A> List<A> synchroList(List<A> l) {
  
  
    return Collections.synchronizedList(l);
  
}



static Object call(Object o) {
  return callF(o);
}

// varargs assignment fixer for a single string array argument
static Object call(Object o, String method, String[] arg) {
  return call(o, method, new Object[] {arg});
}

static Object call(Object o, String method, Object... args) {
  //ret call_cached(o, method, args);
  return call_withVarargs(o, method, args);
}


static <A extends Throwable> A printException(A e) {
  printStackTrace(e);
  return e;
}


static Map synchroHashMap() {
  return synchronizedMap(new HashMap());
}



static <A> A vm_generalMap_getOrCreate(Object key, F0<A> create) {
  return vm_generalMap_getOrCreate(key, f0ToIF0(create));
}

static <A> A vm_generalMap_getOrCreate(Object key, IF0<A> create) {
  Map generalMap = vm_generalMap();
  if (generalMap == null) return null; // must be x30 init
  
  synchronized(generalMap) { // should switch to locks here
    A a =  (A) (vm_generalMap_get(key));
    if (a == null)
      vm_generalMap_put(key, a = create == null ? null : create.get());
    return a;
  }
}




  static <A> A callF_gen(F0<A> f) {
    return f == null ? null : f.get();
  }



  static <A, B> B callF_gen(F1<A, B> f, A a) {
    return f == null ? null : f.get(a);
  }



  static <A> A callF_gen(IF0<A> f) {
    return f == null ? null : f.get();
  }



  static <A, B> B callF_gen(IF1<A, B> f, A a) {
    return f == null ? null : f.get(a);
  }


static <A, B> B callF_gen(A a, IF1<A, B> f) {
  return f == null ? null : f.get(a);
}




  static <A, B, C> C callF_gen(IF2<A, B, C> f, A a, B b) {
    return f == null ? null : f.get(a, b);
  }



  static <A> void callF_gen(VF1<A> f, A a) {
    { if (f != null) f.get(a); }
  }


static <A> void callF_gen(A a, IVF1<A> f) {
  { if (f != null) f.get(a); }
}

static <A> void callF_gen(IVF1<A> f, A a) {
  { if (f != null) f.get(a); }
}

static Object callF_gen(Runnable r) { { if (r != null) r.run(); } return null; }

static Object callF_gen(Object f, Object... args) {
  return callF(f, args);
}


static Object vm_generalMap_get(Object key) {
  return vm_generalMap().get(key);
}


static <A> List<A> immutableEmptyList() {
  return Collections.emptyList();
}


static int[] emptyIntArray_a = new int[0];
static int[] emptyIntArray() { return emptyIntArray_a; }


static char[] emptyCharArray = new char[0];
static char[] emptyCharArray() { return emptyCharArray; }


static double[] emptyDoubleArray = new double[0];
static double[] emptyDoubleArray() { return emptyDoubleArray; }


static short[] emptyShortArray = new short[0];
static short[] emptyShortArray() { return emptyShortArray; }


static <A, B> Map<A, B> immutableEmptyMap() {
  return Collections.emptyMap();
}


static Object[] emptyObjectArray_a = new Object[0];
static Object[] emptyObjectArray() { return emptyObjectArray_a; }


static Symbol emptySymbol_value;

static Symbol emptySymbol() {
  if (emptySymbol_value == null) emptySymbol_value = symbol("");
  return emptySymbol_value;
}


static boolean containsNulls(Collection c) {
  return contains(c, null);
}


static Map similarEmptyMap(Map m) {
  if (m instanceof TreeMap) return new TreeMap(((TreeMap) m).comparator());
  if (m instanceof LinkedHashMap) return new LinkedHashMap();
  
  // default to a hash map
  return new HashMap();
}

static Map similarEmptyMap(Iterable m) {
  if (m instanceof TreeSet) return new TreeMap(((TreeSet) m).comparator());
  if (m instanceof LinkedHashSet) return new LinkedHashMap();
  
  return new HashMap();
}


static <A, B> Set<A> keys(Map<A, B> map) {
  return map == null ? new HashSet() : map.keySet();
}

// convenience shortcut for keys_gen
static Set keys(Object map) {
  return keys((Map) map);
}




  static <A, B> Set<A> keys(IMultiMap<A, B> mm) {
    return mm.keySet();
  }





static <A> List<A> wrapAsList(A[] a) {
  return wrapArrayAsList(a);
}




static <A> IterableIterator<A> emptyItIt() {
  return emptyIterableIterator();
}


static Object endMarker() {
  return iteratorFromFunction_endMarker;
}


// f: func -> A | endMarker
static <A> IterableIterator<A> iff(Object f) {
  return iteratorFromFunction_withEndMarker(f);
}

// can't use type parameter because end marker
static IterableIterator iff(F0 f) {
  return iteratorFromFunction_withEndMarker(f);
}

static <A> IterableIterator iff(IF0 f) {
  return iteratorFromFunction_withEndMarker(f);
}


static int max(int a, int b) { return Math.max(a, b); }
static int max(int a, int b, int c) { return max(max(a, b), c); }
static long max(int a, long b) { return Math.max((long) a, b); }
static long max(long a, long b) { return Math.max(a, b); }
static double max(int a, double b) { return Math.max((double) a, b); }
static float max(float a, float b) { return Math.max(a, b); }
static double max(double a, double b) { return Math.max(a, b); }

static int max(Collection<Integer> c) {
  int x = Integer.MIN_VALUE;
  for (int i : c) x = max(x, i);
  return x;
}

static double max(double[] c) {
  if (c.length == 0) return Double.MIN_VALUE;
  double x = c[0];
  for (int i = 1; i < c.length; i++) x = Math.max(x, c[i]);
  return x;
}

static float max(float[] c) {
  if (c.length == 0) return Float.MAX_VALUE;
  float x = c[0];
  for (int i = 1; i < c.length; i++) x = Math.max(x, c[i]);
  return x;
}

static byte max(byte[] c) {
  byte x = -128;
  for (byte d : c) if (d > x) x = d;
  return x;
}

static short max(short[] c) {
  short x = -0x8000;
  for (short d : c) if (d > x) x = d;
  return x;
}

static int max(int[] c) {
  int x = Integer.MIN_VALUE;
  for (int d : c) if (d > x) x = d;
  return x;
}

static <A extends Comparable<A>> A max(A a, A b) {
  return cmp(a, b) >= 0 ? a : b;
}


static int toInt(Object o) {
  if (o == null) return 0;
  if (o instanceof Number)
    return ((Number) o).intValue();
  if (o instanceof String)
    return parseInt((String) o);
  if (o instanceof Boolean)
    return boolToInt((Boolean) o);
  throw fail("woot not int: " + getClassName(o));
}

static int toInt(long l) {
  if (l != (int) l) throw fail("Too large for int: " + l);
  return (int) l;
}


static String stringIfTrue(boolean b, String s) {
  return b ? s : "";
}


static String rtrim_fromLines(Collection lines) {
  StringBuilder buf = new StringBuilder();
  if (lines != null) {
    boolean first = true;
    for (Object line : lines) {
      if (first) first = false; else buf.append('\n');
      buf.append(str(line));
    }
  }
  return buf.toString();
}


static void swingAndWait(Runnable r) { try {
  if (isAWTThread())
    r.run();
  else
    EventQueue.invokeAndWait(addThreadInfoToRunnable(r));
} catch (Exception __e) { throw rethrow(__e); } }

static Object swingAndWait(final Object f) {
  if (isAWTThread())
    return callF(f);
  else {
    final Var result = new Var();
    swingAndWait(new Runnable() {  public void run() { try { 
      result.set(callF(f));
    
} catch (Exception __e) { throw rethrow(__e); } }  public String toString() { return "result.set(callF(f));"; }});
    return result.get();
  }
}




// requires ugly casting when used (O -> A)
static Object iteratorFromFunction_endMarker = new Object();

// f: func -> A | endMarker
static <A> IterableIterator<A> iteratorFromFunction_withEndMarker(final Object f) {
  class IFF extends IterableIterator<A> {
    A a;
    boolean have, done;
    
    public boolean hasNext() {
      getNext();
      return !done;
    }
    
    public A next() {
      getNext();
      if (done) throw fail();
      A _a = a;
      a = null;
      have = false;
      return _a;
    }
    
    void getNext() {
      if (done || have) return;
      Object o = callF(f);
      if (o == iteratorFromFunction_endMarker)
        { done = true; return; }
      a = (A) o;
      have = true;
    }
  };
  return new IFF();
}

// optimized version for F0 argument; TODO: do same for IF0
static <A> IterableIterator<A> iteratorFromFunction_withEndMarker(final F0 f) {
  return iteratorFromFunction_withEndMarker_f0(f);
}


static <A> A setThreadLocal(ThreadLocal<A> tl, A value) {
  if (tl == null) return null;
  A old = tl.get();
  tl.set(value);
  return old;
}


static int strL(String s) {
  return s == null ? 0 : s.length();
}


static int lCharSequence(CharSequence s) {
  return s == null ? 0 : s.length();
}


static int min(int a, int b) {
  return Math.min(a, b);
}

static long min(long a, long b) {
  return Math.min(a, b);
}

static float min(float a, float b) { return Math.min(a, b); }
static float min(float a, float b, float c) { return min(min(a, b), c); }

static double min(double a, double b) {
  return Math.min(a, b);
}

static double min(double[] c) {
  double x = Double.MAX_VALUE;
  for (double d : c) x = Math.min(x, d);
  return x;
}

static float min(float[] c) {
  float x = Float.MAX_VALUE;
  for (float d : c) x = Math.min(x, d);
  return x;
}

static byte min(byte[] c) {
  byte x = 127;
  for (byte d : c) if (d < x) x = d;
  return x;
}

static short min(short[] c) {
  short x = 0x7FFF;
  for (short d : c) if (d < x) x = d;
  return x;
}

static int min(int[] c) {
  int x = Integer.MAX_VALUE;
  for (int d : c) if (d < x) x = d;
  return x;
}


static void clear(Collection c) {
  if (c != null) c.clear();
}

static void clear(Map map) {
  if (map != null) map.clear();
}


static <A, B> void put(Map<A, B> map, A a, B b) {
  if (map != null) map.put(a, b);
}

static <A> void put(List<A> l, int i, A a) {
  if (l != null && i >= 0 && i < l(l)) l.set(i, a);
}


static Class<?> _getClass(String name) {
  try {
    return Class.forName(name);
  } catch (ClassNotFoundException e) {
    return null; // could optimize this
  }
}

static Class _getClass(Object o) {
  return o == null ? null
    : o instanceof Class ? (Class) o : o.getClass();
}

static Class _getClass(Object realm, String name) {
  try {
    return classLoaderForObject(realm).loadClass(classNameToVM(name));
  } catch (ClassNotFoundException e) {
    return null; // could optimize this
  }
}


static <A, B> B syncMapGet2(Map<A, B> map, A a) {
  if (map == null) return null;
  synchronized(collectionMutex(map)) {
    return map.get(a);
  }
}

static <A, B> B syncMapGet2(A a, Map<A, B> map) {
  return syncMapGet2(map, a);
}


static boolean isSubtypeOf(Class a, Class b) {
  return a != null && b != null && b.isAssignableFrom(a); // << always hated that method, let's replace it!
}


static Set<String> reflection_classesNotToScan_value = litset(
  "jdk.internal.loader.URLClassPath"
);

static Set<String> reflection_classesNotToScan() {
  return reflection_classesNotToScan_value;
}


static HashMap<String, List<Method>> callMC_cache = new HashMap();
static String callMC_key;
static Method callMC_value;

// varargs assignment fixer for a single string array argument
static Object callMC(String method, String[] arg) {
  return callMC(method, new Object[] {arg});
}

static Object callMC(String method, Object... args) { try {
  Method me;
  if (callMC_cache == null) callMC_cache = new HashMap(); // initializer time workaround
  synchronized(callMC_cache) {
    me = method == callMC_key ? callMC_value : null;
  }
  if (me != null) try {
    return invokeMethod(me, null, args);
  } catch (IllegalArgumentException e) {
    throw new RuntimeException("Can't call " + me + " with arguments " + classNames(args), e);
  }

  List<Method> m;
  synchronized(callMC_cache) {
    m = callMC_cache.get(method);
  }
  if (m == null) {
    if (callMC_cache.isEmpty()) {
      callMC_makeCache();
      m = callMC_cache.get(method);
    }
    if (m == null) throw fail("Method named " + method + " not found in main");
  }
  int n = m.size();
  if (n == 1) {
    me = m.get(0);
    synchronized(callMC_cache) {
      callMC_key = method;
      callMC_value = me;
    }
    try {
      return invokeMethod(me, null, args);
    } catch (IllegalArgumentException e) {
      throw new RuntimeException("Can't call " + me + " with arguments " + classNames(args), e);
    }
  }
  for (int i = 0; i < n; i++) {
    me = m.get(i);
    if (call_checkArgs(me, args, false))
      return invokeMethod(me, null, args);
  }
  throw fail("No method called " + method + " with arguments (" + joinWithComma(getClasses(args)) + ") found in main");
} catch (Exception __e) { throw rethrow(__e); } }

static void callMC_makeCache() {
  synchronized(callMC_cache) {
    callMC_cache.clear();
    Class _c = (Class) mc(), c = _c;
    while (c != null) {
      for (Method m : c.getDeclaredMethods())
        if ((m.getModifiers() & java.lang.reflect.Modifier.STATIC) != 0) {
          makeAccessible(m);
          multiMapPut(callMC_cache, m.getName(), m);
        }
      c = c.getSuperclass();
    }
  }
}


public static <A> String join(String glue, Iterable<A> strings) {
  if (strings == null) return "";
  if (strings instanceof Collection) {
    if (((Collection) strings).size() == 1) return str(first((Collection) strings));
  }
  StringBuilder buf = new StringBuilder();
  Iterator<A> i = strings.iterator();
  if (i.hasNext()) {
    buf.append(i.next());
    while (i.hasNext())
      buf.append(glue).append(i.next());
  }
  return buf.toString();
}

public static String join(String glue, String... strings) {
  return join(glue, Arrays.asList(strings));
}

public static String join(String glue, Object... strings) {
  return join(glue, Arrays.asList(strings));
}

static <A> String join(Iterable<A> strings) {
  return join("", strings);
}

static <A> String join(Iterable<A> strings, String glue) {
  return join(glue, strings);
}

public static String join(String[] strings) {
  return join("", strings);
}


static String join(String glue, Pair p) {
  return p == null ? "" : str(p.a) + glue + str(p.b);
}



static List<String> getClassNames(Collection l) {
  List<String> out = new ArrayList();
  if (l != null) for (Object o : l)
    out.add(o == null ? null : getClassName(o));
  return out;
}


static boolean startsWith(String a, String b) {
  return a != null && a.startsWith(unnull(b));
}

static boolean startsWith(String a, char c) {
  return nemptyString(a) && a.charAt(0) == c;
}


  static boolean startsWith(String a, String b, Matches m) {
    if (!startsWith(a, b)) return false;
    if (m != null) m.m = new String[] {substring(a, strL(b))};
    return true;
  }


static boolean startsWith(List a, List b) {
  if (a == null || listL(b) > listL(a)) return false;
  for (int i = 0; i < listL(b); i++)
    if (neq(a.get(i), b.get(i)))
      return false;
  return true;
}




static boolean domainIsUnder(String domain, String mainDomain) {
  return eqic(domain, mainDomain) || ewic(domain, "." + mainDomain);
}


static String theAGIBlueDomain() {
  return "agi.blue";
}


static Object callFunction(Object f, Object... args) {
  return callF(f, args);
}


static Throwable _storeException_value;

static void _storeException(Throwable e) {
  _storeException_value = e;
}


static Map vm_generalMap_map;

static Map vm_generalMap() {
  if (vm_generalMap_map == null)
    
    
    
    vm_generalMap_map = (Map) get(javax(), "generalMap");
    
    
  return vm_generalMap_map;
}


static Object vm_generalMap_put(Object key, Object value) {
  return mapPutOrRemove(vm_generalMap(), key, value);
}


static <A> Set<A> syncIdentityHashSet() {
  return (Set) synchronizedSet(identityHashSet());
}


static Map syncHashMap() {
  return synchroHashMap();
}


static Class __javax;

static Class getJavaX() { try {
  
  return __javax;
} catch (Exception __e) { throw rethrow(__e); } }

static void __setJavaX(Class j) {
  __javax = j;
  _onJavaXSet();
}


static Object call_withVarargs(Object o, String methodName, Object... args) { try {
  if (o == null) return null;
  
  if (o instanceof Class) {
    Class c = (Class) o;
    _MethodCache cache = callOpt_getCache(c);
    
    Method me = cache.findStaticMethod(methodName, args);
    if (me != null)
      return invokeMethod(me, null, args);
      
    // try varargs
    List<Method> methods = cache.cache.get(methodName);
    if (methods != null) methodSearch: for (Method m : methods) {
      { if (!(m.isVarArgs())) continue; }
      { if (!(isStaticMethod(m))) continue; }
      Object[] newArgs = massageArgsForVarArgsCall(m, args);
      if (newArgs != null)
        return invokeMethod(m, null, newArgs);
    }
    
    throw fail("Method " + c.getName() + "." + methodName + "(" + joinWithComma(classNames(args)) + ") not found");
  } else {
    Class c = o.getClass();
    _MethodCache cache = callOpt_getCache(c);

    Method me = cache.findMethod(methodName, args);
    if (me != null)
      return invokeMethod(me, o, args);
      
    // try varargs
    List<Method> methods = cache.cache.get(methodName);
    if (methods != null) methodSearch: for (Method m : methods) {
      { if (!(m.isVarArgs())) continue; }
      Object[] newArgs = massageArgsForVarArgsCall(m, args);
      if (newArgs != null)
        return invokeMethod(m, o, newArgs);
    }
    
    throw fail("Method " + c.getName() + "." + methodName + "(" + joinWithComma(classNames(args)) + ") not found");
  }
} catch (Exception __e) { throw rethrow(__e); } }


static <A extends Throwable> A printStackTrace(A e) {
  // we go to system.out now - system.err is nonsense
  if (e != null) print(getStackTrace(e));
  return e;
}

static void printStackTrace() {
  printStackTrace(new Throwable());
}

static void printStackTrace(String msg) {
  printStackTrace(new Throwable(msg));
}

static void printStackTrace(String msg, Throwable e) {
  printStackTrace(new Throwable(msg, e));
}


static Map synchronizedMap() {
  return synchroMap();
}

static <A, B> Map<A, B> synchronizedMap(Map<A, B> map) {
  return synchroMap(map);
}


static <A> IF0<A> f0ToIF0(F0<A> f) {
  return f == null ? null : () -> f.get();
}




static WeakHasherMap<Symbol, Boolean> symbol_map = new WeakHasherMap(new Hasher<Symbol>() {
  public int hashCode(Symbol symbol) { return symbol.text.hashCode(); }
  public boolean equals(Symbol a, Symbol b) {
    if (a == null) return b == null;
    return b != null && eq(a.text, b.text);
  }
});



static Symbol symbol(String s) {
  
  
  if (s == null) return null;
  synchronized(symbol_map) {
    // TODO: avoid object creation by passing the string to findKey
    Symbol symbol = new Symbol(s, true);
    Symbol existingSymbol = symbol_map.findKey(symbol);
    if (existingSymbol == null)
      symbol_map.put(existingSymbol = symbol, true);
    
      
    return existingSymbol;
  }
  
}

static Symbol symbol(CharSequence s) {
  if (s == null) return null;
  
  
  if (s instanceof Symbol) return (Symbol) s;
  if (s instanceof String) return symbol((String) s);
  return symbol(str(s));
  
}

static Symbol symbol(Object o) {
  return symbol((CharSequence) o);
}


static boolean contains(Collection c, Object o) {
  return c != null && c.contains(o);
}

static boolean contains(Iterable it, Object a) {
  if (it != null)
    for (Object o : it)
      if (eq(a, o))
        return true;
  return false;
}

static boolean contains(Object[] x, Object o) {
  if (x != null)
    for (Object a : x)
      if (eq(a, o))
        return true;
  return false;
}

static boolean contains(String s, char c) {
  return s != null && s.indexOf(c) >= 0;
}

static boolean contains(String s, String b) {
  return s != null && s.indexOf(b) >= 0;
}

static boolean contains(BitSet bs, int i) {
  return bs != null && bs.get(i);
}




static boolean contains(Rect r, Pt p) { return rectContains(r, p); }



static <A> List<A> wrapArrayAsList(A[] a) {
  return a == null ? null : Arrays.asList(a);
}


static IterableIterator emptyIterableIterator_instance = new IterableIterator() {
  public Object next() { throw fail(); }
  public boolean hasNext() { return false; }
};

static <A> IterableIterator<A> emptyIterableIterator() {
  return emptyIterableIterator_instance; 
}


static int cmp(Number a, Number b) {
  return a == null ? b == null ? 0 : -1 : cmp(a.doubleValue(), b.doubleValue());
}

static int cmp(double a, double b) {
  return a < b ? -1 : a == b ? 0 : 1;
}

static int cmp(int a, int b) {
  return a < b ? -1 : a == b ? 0 : 1;
}

static int cmp(long a, long b) {
  return a < b ? -1 : a == b ? 0 : 1;
}

static int cmp(Object a, Object b) {
  if (a == null) return b == null ? 0 : -1;
  if (b == null) return 1;
  return ((Comparable) a).compareTo(b);
}


static int parseInt(String s) {
  return emptyString(s) ? 0 : Integer.parseInt(s);
}

static int parseInt(char c) {
  return Integer.parseInt(str(c));
}


static int boolToInt(boolean b) {
  return b ? 1 : 0;
}


static Runnable addThreadInfoToRunnable(final Object r) {
  final Object info = _threadInfo();
  return info == null ? asRunnable(r) : new Runnable() {  public void run() { try {  _inheritThreadInfo(info); callF(r); 
} catch (Exception __e) { throw rethrow(__e); } }  public String toString() { return "_inheritThreadInfo(info); callF(r);"; }};
}




static <A> IterableIterator<A> iteratorFromFunction_withEndMarker_f0(final F0<A> f) {
  class IFF2 extends IterableIterator<A> {
    A a;
    boolean have, done;
    
    public boolean hasNext() {
      getNext();
      return !done;
    }
    
    public A next() {
      getNext();
      if (done) throw fail();
      A _a = a;
      a = null;
      have = false;
      return _a;
    }
    
    void getNext() {
      if (done || have) return;
      Object o = f.get();
      if (o == iteratorFromFunction_endMarker)
        { done = true; return; }
      a = (A) o;
      have = true;
    }
  };
  return new IFF2();
}


static ClassLoader classLoaderForObject(Object o) {
  if (o instanceof ClassLoader) return ((ClassLoader) o);
  if (o == null) return null;
  return _getClass(o).getClassLoader();
}


// Note: This is actually broken. Inner classes must stay with a $ separator
static String classNameToVM(String name) {
  return name.replace(".", "$");
}


static <A> HashSet<A> litset(A... items) {
  return lithashset(items);
}


static <A> String joinWithComma(Collection<A> c) {
  return join(", ", c);
}

static String joinWithComma(Object... c) {
  return join(", ", c);
}

static String joinWithComma(String... c) {
  return join(", ", c);
}


static String joinWithComma(Pair p) {
  return p == null ? "" : joinWithComma(str(p.a), str(p.b));
}



static List<Class> getClasses(Object[] array) {
  List<Class> l = emptyList(l(array));
  for (Object o : array) l.add(_getClass(o));
  return l;
}


static <A, B> void multiMapPut(Map<A, List<B>> map, A a, B b) {
  List<B> l = map.get(a);
  if (l == null)
    map.put(a, l = new ArrayList());
  l.add(b);
}


static <A, B> void multiMapPut(MultiMap<A, B> mm, A key, B value) {
  if (mm != null && key != null && value != null) mm.put(key, value);
}



static String unnull(String s) {
  return s == null ? "" : s;
}

static <A> Collection<A> unnull(Collection<A> l) {
  return l == null ? emptyList() : l;
}

static <A> List<A> unnull(List<A> l) { return l == null ? emptyList() : l; }
static int[] unnull(int[] l) { return l == null ? emptyIntArray() : l; }
static char[] unnull(char[] l) { return l == null ? emptyCharArray() : l; }
static double[] unnull(double[] l) { return l == null ? emptyDoubleArray() : l; }

static <A, B> Map<A, B> unnull(Map<A, B> l) {
  return l == null ? emptyMap() : l;
}

static <A> Iterable<A> unnull(Iterable<A> i) {
  return i == null ? emptyList() : i;
}

static <A> A[] unnull(A[] a) {
  return a == null ? (A[]) emptyObjectArray() : a;
}

static BitSet unnull(BitSet b) {
  return b == null ? new BitSet() : b;
}


static Pt unnull(Pt p) {
  return p == null ? new Pt() : p;
}


//ifclass Symbol

static Symbol unnull(Symbol s) {
  return s == null ? emptySymbol() : s;
}
//endif



static <A, B> Pair<A, B> unnull(Pair<A, B> p) {
  return p != null ? p : new Pair(null, null);
}


static int unnull(Integer i) { return i == null ? 0 : i; }
static long unnull(Long l) { return l == null ? 0L : l; }
static double unnull(Double l) { return l == null ? 0.0 : l; }


static boolean nemptyString(String s) {
  return s != null && s.length() > 0;
}


static int listL(Collection l) {
  return l == null ? 0 : l.size();
}


static boolean neq(Object a, Object b) {
  return !eq(a, b);
}


static boolean eqic(String a, String b) {
  
  
    if ((a == null) != (b == null)) return false;
    if (a == null) return true;
    return a.equalsIgnoreCase(b);
  
}


static boolean eqic(Symbol a, Symbol b) {
  return eq(a, b);
}

static boolean eqic(Symbol a, String b) {
  return eqic(asString(a), b);
}


static boolean eqic(char a, char b) {
  if (a == b) return true;
  
    char u1 = Character.toUpperCase(a);
    char u2 = Character.toUpperCase(b);
    if (u1 == u2) return true;
  
  return Character.toLowerCase(u1) == Character.toLowerCase(u2);
}


static boolean ewic(String a, String b) {
  return endsWithIgnoreCase(a, b);
}


static boolean ewic(String a, String b, Matches m) {
  return endsWithIgnoreCase(a, b, m);
}



static <A, B> B mapPutOrRemove(Map<A, B> map, A key, B value) {
  if (map != null && key != null)
    if (value != null) return map.put(key, value);
    else return map.remove(key);
  return null;
}


static <A> Set<A> synchronizedSet() {
  return synchroHashSet();
}

static <A> Set<A> synchronizedSet(Set<A> set) {
  
  
    return Collections.synchronizedSet(set);
  
}


static <A> Set<A> identityHashSet() {
  return Collections.newSetFromMap(new IdentityHashMap());
}


static void _onJavaXSet() {}


static final Map<Class, _MethodCache> callOpt_cache = newDangerousWeakHashMap();

static Object callOpt_cached(Object o, String methodName, Object... args) { try {
  if (o == null) return null;
  
  if (o instanceof Class) {
    Class c = (Class) o;
    _MethodCache cache = callOpt_getCache(c);
    
    // TODO: (super-rare) case where method exists static and non-static
    // with different args
    
    Method me = cache.findMethod(methodName, args);
    if (me == null || (me.getModifiers() & Modifier.STATIC) == 0) return null;
    return invokeMethod(me, null, args);
  } else {
    Class c = o.getClass();
    _MethodCache cache = callOpt_getCache(c);

    Method me = cache.findMethod(methodName, args);
    if (me == null) return null;
    return invokeMethod(me, o, args);
  }
} catch (Exception __e) { throw rethrow(__e); } }

// no longer synchronizes! (see #1102990)
static _MethodCache callOpt_getCache(Class c) {
  _MethodCache cache = callOpt_cache.get(c);
  if (cache == null)
    callOpt_cache.put(c, cache = new _MethodCache(c));
  return cache;
}


static boolean isStaticMethod(Method m) {
  return methodIsStatic(m);
}


static Object[] massageArgsForVarArgsCall(Executable m, Object[] args) {
  Class<?>[] types = m.getParameterTypes();
  int n = types.length-1, nArgs = l(args);
  if (nArgs < n) return null;
  for (int i = 0; i < n; i++)
    if (!argumentCompatibleWithType(args[i], types[i]))
      return null;
  Class varArgType = types[n].getComponentType();
  for (int i = n; i < nArgs; i++)
    if (!argumentCompatibleWithType(args[i], varArgType))
      return null;
  Object[] newArgs = new Object[n+1];
  arraycopy(args, 0, newArgs, 0, n);
  
  // TODO: optimize
  
  int nVarArgs = nArgs-n;
  Object varArgs = Array.newInstance(varArgType, nVarArgs);
  for (int i = 0; i < nVarArgs; i++)
    Array.set(varArgs, i, args[n+i]);
    
  newArgs[n] = varArgs;
  return newArgs;
}


static boolean rectContains(int x1, int y1, int w, int h, Pt p) {
  return p.x >= x1 && p.y >= y1 && p.x < x1+w && p.y < y1+h;
}

static boolean rectContains(Rect a, Rect b) {
  return b.x >= a.x && b.y >= a.y && b.x2() <= a.x2() && b.y2() <= a.y2();
}

static boolean rectContains(Rect a, Rectangle b) {
  return rectContains(a, toRect(b));
}

static boolean rectContains(Rect a, int x, int y) {
  return a != null && a.contains(x, y);
}

static boolean rectContains(Rect a, Pt p) {
  return a != null && p != null && a.contains(p);
}


static boolean emptyString(String s) {
  return s == null || s.length() == 0;
}


static List<VF1<Map>> _threadInfo_makers = synchroList();

static Object _threadInfo() {
  if (empty(_threadInfo_makers)) return null;
  HashMap map = new HashMap();
  pcallFAll(_threadInfo_makers, map);
  return map;
}


static Runnable asRunnable(Object o) {
  return toRunnable(o);
}




static void _inheritThreadInfo(Object info) {
  _threadInheritInfo(info);
}




static <A> HashSet<A> lithashset(A... items) {
  HashSet<A> set = new HashSet();
  for (A a : items) set.add(a);
  return set;
}


static Map emptyMap() {
  return new HashMap();
}


static String asString(Object o) {
  return o == null ? null : o.toString();
}


static boolean endsWithIgnoreCase(String a, String b) {
  int la = l(a), lb = l(b);
  return la >= lb && regionMatchesIC(a, la-lb, b, 0, lb);
}


static boolean endsWithIgnoreCase(String a, String b, Matches m) {
  if (!endsWithIgnoreCase(a, b)) return false;
  if (m != null)
    m.m = new String[] { substring(a, 0, l(a)-l(b)) };
  return true;
}



static <A> Set<A> synchroHashSet() {
  return synchronizedSet(new HashSet<A>());
}



static boolean methodIsStatic(Method m) {
  return (m.getModifiers() & Modifier.STATIC) != 0;
}


static boolean argumentCompatibleWithType(Object arg, Class type) {
  return arg == null ? !type.isPrimitive() : isInstanceX(type, arg);
}


static void arraycopy(Object[] a, Object[] b) {
  if (a != null && b != null)
    arraycopy(a, 0, b, 0, Math.min(a.length, b.length));
}

static void arraycopy(Object src, int srcPos, int destPos, int n) { arraycopy(src, srcPos, src, destPos, n); }
static void arraycopy(Object src, int srcPos, Object dest, int destPos, int n) {
  if (n != 0)
    System.arraycopy(src, srcPos, dest, destPos, n);
}




static Rect toRect(Rectangle r) {
  return r == null ? null : new Rect(r);
}

static Rect toRect(RectangularShape r) {
  return r == null ? null : toRect(r.getBounds());
}



static Rect toRect(Rect r) { return r; }


static void pcallFAll(Collection l, Object... args) {
  if (l != null) for (Object f : cloneList(l)) pcallF(f, args);
}

static void pcallFAll(Iterator it, Object... args) {
  while (it.hasNext()) pcallF(it.next(), args);
}


static Runnable toRunnable(final Object o) {
  if (o == null) return null;
  if (o instanceof Runnable) return (Runnable) o;
  
  if (o instanceof String) throw fail("callF_legacy");
  
  return new Runnable() {  public void run() { try {  callF(o) ;
} catch (Exception __e) { throw rethrow(__e); } }  public String toString() { return "callF(o)"; }};
}


static List<VF1<Map>> _threadInheritInfo_retrievers = synchroList();

static void _threadInheritInfo(Object info) {
  if (info == null) return;
  pcallFAll(_threadInheritInfo_retrievers, (Map) info);
}




static boolean regionMatchesIC(String a, int offsetA, String b, int offsetB, int len) {
  
  
    return a != null && a.regionMatches(true, offsetA, b, offsetB, len);
  
}


static int iround(double d) {
  return (int) Math.round(d);
}


static int iround(Number n) {
  return iround(toDouble(n));
}



static Object pcallF(Object f, Object... args) {
  return pcallFunction(f, args);
}


static <A> A pcallF(F0<A> f) {
  try { return f == null ? null : f.get(); } catch (Throwable __e) { printStackTrace(__e); } return null;
}



static <A, B> B pcallF(F1<A, B> f, A a) {
  try { return f == null ? null : f.get(a); } catch (Throwable __e) { printStackTrace(__e); } return null;
}



static <A> void pcallF(VF1<A> f, A a) {
  try {
    { if (f != null) f.get(a); }
  } catch (Throwable __e) { printStackTrace(__e); }
}


static Object pcallF(Runnable r) {
  try { { if (r != null) r.run(); } } catch (Throwable __e) { printStackTrace(__e); } return null;
}

static <A> A pcallF(IF0<A> f) {
  try { return f == null ? null : f.get(); } catch (Throwable __e) { printStackTrace(__e); } return null;
}

static <A, B> B pcallF(IF1<A, B> f, A a) {
  try { return f == null ? null : f.get(a); } catch (Throwable __e) { printStackTrace(__e); } return null;
}





static double toDouble(Object o) {
  if (o instanceof Number)
    return ((Number) o).doubleValue();
  if (o instanceof BigInteger)
    return ((BigInteger) o).doubleValue();
  if (o instanceof String)
    return parseDouble((String) o);
  if (o == null) return 0.0;
  throw fail(o);
}


static Object pcallFunction(Object f, Object... args) {
  try { return callFunction(f, args); } catch (Throwable __e) { printStackTrace(__e); }
  return null;
}




static double parseDouble(String s) {
  return empty(s) ? 0.0 : Double.parseDouble(s);
}




static abstract class VF1<A> implements IVF1<A> {
  public abstract void get(A a);
}
// immutable, has strong refs
// Do not run in a synchronized block - it goes wrong in the presence
// of elaborate classloaders (like in Gazelle BEA)
// see #1102990 and #1102991

final static class _MethodCache {
  final Class c;
  final HashMap<String, List<Method>> cache = new HashMap();
  
  _MethodCache(Class c) {
  this.c = c; _init(); }
  
  void _init() {
    Class _c = c;
    java.lang.Module myModule = getClass().getModule();
    boolean anyHiddenClasses = false;
    
    while (_c != null) {
      boolean exported = classIsExportedTo(_c, myModule);
       
      
      if (!exported)
        anyHiddenClasses = true;
      else
        for (Method m : _c.getDeclaredMethods())
          if ((anyHiddenClasses || !isAbstract(m))
            && !reflection_isForbiddenMethod(m))
            multiMapPut(cache, m.getName(), makeAccessible(m));

      _c = _c.getSuperclass();
    }
    
    // add default methods - this might lead to a duplication
    // because the overridden method is also added, but it's not
    // a problem except for minimal performance loss.
    // If any classes in the hierarchy were inaccessible, we add
    // all interface methods (see test_callForbiddenMethodByReflection for a test)
    
    for (Class intf : allInterfacesImplementedBy(c))
      for (Method m : intf.getDeclaredMethods())
        if ((anyHiddenClasses || m.isDefault()) && !reflection_isForbiddenMethod(m))
          multiMapPut(cache, m.getName(), makeAccessible(m));

     
  }
  
  // Returns only matching methods
  Method findMethod(String method, Object[] args) { try {
    List<Method> m = cache.get(method);
     
    if (m == null) return null;
    int n = m.size();
    for (int i = 0; i < n; i++) {
      Method me = m.get(i);
      if (call_checkArgs(me, args, false))
        return me;
    }
    return null;
  } catch (Exception __e) { throw rethrow(__e); } }
  
  Method findStaticMethod(String method, Object[] args) { try {
    List<Method> m = cache.get(method);
    if (m == null) return null;
    int n = m.size();
    for (int i = 0; i < n; i++) {
      Method me = m.get(i);
      if (isStaticMethod(me) && call_checkArgs(me, args, false))
        return me;
    }
    return null;
  } catch (Exception __e) { throw rethrow(__e); } }
  
  //Cl<Method> allMethods() { ret allValues(cache); }
}
static class PtSet extends java.util.AbstractSet<Pt> {
  final CompactLongSet set;
  
  PtSet() { set = new CompactLongSet(); }
  PtSet(int size) { set = new CompactLongSet(size); }
  
  PtSet(Iterable<Pt> l) {
    this();
    if (l != null) for (Pt p : l) add(p);
  }
  
  PtSet(Collection<Pt> l) {
    this(l(l));
    if (l != null) for (Pt p : l) add(p);
  }
  
  public int size() { return set.size(); }
  
  public boolean contains(Pt p) {
    return set.contains(ptToLong(p));
  }
  
  public boolean contains(int x, int y) {
    return set.contains(ptToLong(x, y));
  }
  
  public boolean add(Pt p) {
    return set.add(ptToLong(p));
  }
  
  public boolean add(int x, int y) {
    return set.add(ptToLong(x, y));
  }
  
  public boolean remove(Pt p) {
    return set.remove(ptToLong(p));
  }
  
  public boolean remove(int x, int y) {
    return set.remove(ptToLong(x, y));
  }
  
  public void clear() { set.clear(); }
  
  public Iterator<Pt> iterator() {
    RenamedLongIterator it = set.iterator();
    return new IterableIterator<Pt>() {
      public boolean hasNext() {
        return it.hasNext();
      }
      
      public Pt next() {
        return ptFromLong(it.nextLong());
      }
      
      public void remove() {
        it.remove();
      }
    };
  }
}
static class Matches {
  String[] m;
  
  Matches() {}
  Matches(String... m) {
  this.m = m;}
  
  String get(int i) { return i < m.length ? m[i] : null; }
  String unq(int i) { return unquote(get(i)); }
  
  String tlc(int i) { return unq(i).toLowerCase(); }
  boolean bool(int i) { return "true".equals(unq(i)); }
  String rest() { return m[m.length-1]; } // for matchStart
  int psi(int i) { return Integer.parseInt(unq(i)); }
  
  public String toString() { return "Matches(" + joinWithComma(quoteAll(asList(m))) + ")"; }
  
  public int hashCode() { return _hashCode(toList(m)); }
  public boolean equals(Object o) { return o instanceof Matches && arraysEqual(m, ((Matches) o).m); }
}

// A "mesh" is a set of points ("anchors") connected through curves.
// An anchor is either
// -the end of a curve
// -an intersection of curves
// -or a randomly chosen point along a curve (type 3)

// A type 3 anchor can be necessary to define an "o" shape
// (because such a shape doesn't have an anchor point per se,
// so we just choose one point along the ring).

// Sometimes however, a type 3 anchor is an artifact of the mesh
// finding process and can be eliminated, reducing the anchor and
// curve count by 1.

static class G22Mesh {
  LinkedHashMap<Pt, Anchor> anchorMap = new LinkedHashMap(); // sorted by index
   final public Set<Curve> getCurves(){ return curves(); }
public Set<Curve> curves() { return curves; }
 Set<Curve> curves = new HashSet(); // in no particular order
  
  static class Curve {
    Anchor start, end;
    OnePathWithOrigin path; // origin = start.pt
    
    Curve(Anchor start, Anchor end, List<Pt> points) {
  this.end = end;
  this.start = start;
      path = new OnePathWithOrigin(points, false);
      start.outgoingCurves.add(this);
      end.incomingCurves.add(this);
    }
    
    public String toString() {
      return "Curve of length " + n2(path.nSteps())
        + " connecting " + (start == null ? null : start.shortToString() + " and " + (end == null ? null : end.shortToString()));
    }
    
    // This counts one of the anchors, but not the other.
    // So if the anchors are right next to each other,
    // the curve's length is 1.
    int length() { return path.nSteps(); }
    
    List<Anchor> anchors() { return ll(start, end); }
  }
  
  static class Anchor {
    int index; // every anchor gets a number starting from one
    Pt pt;
    List<Curve> outgoingCurves = new ArrayList();
    List<Curve> incomingCurves = new ArrayList();
    
    Anchor(int index, Pt pt) {
  this.pt = pt;
  this.index = index;}
    
    int arity() { return l(outgoingCurves) + l(incomingCurves); }
    
    String shortToString() {
      return "Anchor " + index + " at " + pt;
    }
    
    public String toString() {
      List<Integer> connections = sorted(map(connectedToAnchors(), a -> a.index));
      return shortToString() + ", arity " + arity()
        + stringIf(isRingAnchor(), " [arbitrarily chosen ring anchor]")
        + (empty(connections) ? "" : ", connected to " + joinWithComma(connections));
    }
    
    Set<Anchor> connectedToAnchors() {
      return joinSets(
        map(outgoingCurves, c -> c.end),
        map(incomingCurves, c -> c.start));
    }

    // The ring case where we just randomly select an anchor    
    boolean isRingAnchor() {
      return l(outgoingCurves) == 1 && l(incomingCurves) == 1
        && first(outgoingCurves) == first(incomingCurves);
    }
  }
  
  Collection<Pt> anchorPts() { return keys(anchorMap); }
  Collection<Anchor> anchors() { return values(anchorMap); }
  Anchor getAnchor(Pt p) { return anchorMap.get(p); }
  
  // Internal structure sanity check 
  void checkArities() {
    MultiMap<Anchor, Curve> outgoing = new MultiMap();
    MultiMap<Anchor, Curve> incoming = new MultiMap();
    
    for (Curve curve : curves) {
      outgoing.add(curve.start, curve);
      if (!anchorMap.containsKey(curve.start.pt))
        throw fail("Start of curve not found: " + curve);
      incoming.add(curve.end, curve);
      if (!anchorMap.containsKey(curve.end.pt))
        throw fail("End of curve not found: " + curve);
    }
     
    for (Anchor anchor : anchors()) {
      assertSetEquals(anchor + " outgoing", outgoing.get(anchor), anchor.outgoingCurves);
      assertSetEquals(anchor + " incoming", incoming.get(anchor), anchor.incomingCurves);
    }
  }
  
  Anchor newAnchor(Pt p) {  
    Anchor anchor = new Anchor(l(anchorMap)+1, p);
    anchorMap.put(p, anchor);
    return anchor;
  }
  
  void removeAnchor(Anchor anchor) {
    anchorMap.remove(anchor.pt);
  }
  
  void addCurve(Curve curve) {
    curves.add(curve);
  }
  
  void removeCurve(Curve curve) {
    curves.remove(curve);
    curve.start.outgoingCurves.remove(curve);
    curve.end.incomingCurves.remove(curve);
  }
}
// for the version with MasterSymbol (used WAY back in "Smart Bot"!) see #1010608

static class Symbol implements CharSequence {
  String text;
  
  Symbol() {}
  Symbol(String text, boolean dummy) {
  this.text = text;} // weird signature to prevent accidental calling
  
  public int hashCode() { return _hashCode(text); }
  public String toString() { return text; }
  public boolean equals(Object o) {
    return this == o;
  }

  // implementation of CharSequence methods
  
  public int length() { return text.length(); }
  public char charAt(int index) { return text.charAt(index); }
  public CharSequence subSequence(int start, int end) {
    return text.substring(start, end);
  }
}
static class Var<A> implements IVar<A>, ISetter<A> {
  Var() {}
  Var(A v) {
  this.v = v;}

  
  
  A v; // you can access this directly if you use one thread
  
  public synchronized void set(A a) {
    if (v != a) {
      v = a;
      notifyAll();
    }
  }
  
  public synchronized A get() { return v; }
  public synchronized boolean has() { return v != null; }
  public void clear() { set(null); }

public String toString() { return str(this.get()); }
}
interface IImageRegion<Img extends WidthAndHeight> {
  // REQUIRED METHODS
  
  // smallest rectangle that all of the region's pixels are contained in
  public Rect bounds();
  
  public IterableIterator<Pt> pixelIterator();
  public boolean contains(int x, int y);
  
  // convenience methods
  
  public default boolean contains(Pt p) { return contains(p.x, p.y); }
  
  // OPTIONAL METHODS
  
  // get whole image that the region refers to
  public default Img image() { return null; }
  
  // which object made this
  public default Object creator() { return null; }
  
  public default int indexInCreator() { return 0; }
  
  public default int numberOfPixels() { return l(pixelIterator()); }
  public default Pt firstPixel() { return first(pixelIterator()); }
  
  // gets the region's color (what exactly this means is defined
  // by the crea)
  public default RGB color() { return null; }
  
  public default int brightness() { return -1; }
}
static class MultiMap<A,B> implements IMultiMap<A, B> {
  Map<A, List<B>> data = new HashMap<A, List<B>>();
  int fullSize;
  
  MultiMap() {}
  MultiMap(boolean useTreeMap) { if (useTreeMap) data = new TreeMap(); }
  MultiMap(MultiMap<A, B> map) { putAll(map); }
  MultiMap(Map<A, List<B>> data) {
  this.data = data;}

  void put(A key, B value) { synchronized(data) {
    List<B> list = data.get(key);
    if (list == null)
      data.put(key, list = _makeEmptyList());
    list.add(value);
    ++fullSize;
  }}

  void add(A key, B value) { put(key, value); }

  void addAll(A key, Collection<B> values) { putAll(key, values); }
  
  void addAllIfNotThere(A key, Collection<B> values) { synchronized(data) {
    for (B value : values)
      setPut(key, value);
  }}
  
  void setPut(A key, B value) { synchronized(data) {
    if (!containsPair(key, value))
      put(key, value);
  }}
  
  boolean containsPair(A key, B value) { synchronized(data) {
    return get(key).contains(value);
  }}
  
  void putAll(Collection<A> keys, B value) { synchronized(data) {
    for (A key : unnullForIteration(keys))
      put(key, value);
  }}

  void putAll(A key, Collection<B> values) { synchronized(data) {
    if (nempty(values)) getActual(key).addAll(values);
  }}

  void putAll(Iterable<Pair<A, B>> pairs) { synchronized(data) {
    for (Pair<A, B> p : unnullForIteration(pairs))
      put(p.a, p.b);
  }}
  
  void removeAll(A key, Collection<B> values) { synchronized(data) {
    for (B value : values)
      remove(key, value);
  }}
  
  public List<B> get(A key) { synchronized(data) {
    List<B> list = data.get(key);
    return list == null ? Collections.<B> emptyList() : list;
  }}
  
  List<B> getOpt(A key) { synchronized(data) {
    return data.get(key);
  }}

  List<B> getAndClear(A key) { synchronized(data) {
    List<B> l = cloneList(data.get(key));
    remove(key);
    return l;
  }}
  
  // returns actual mutable live list
  // creates the list if not there
  List<B> getActual(A key) { synchronized(data) {
    List<B> list = data.get(key);
    if (list == null)
      data.put(key, list = _makeEmptyList());
    return list;
  }}
 
  void clean(A key) { synchronized(data) {
    List<B> list = data.get(key);
    if (list != null && list.isEmpty()) {
      fullSize -= l(list);
      data.remove(key);
    }
  }}

  final public Set<A> keys(){ return keySet(); }
public Set<A> keySet() { synchronized(data) {
    return data.keySet();
  }}

  void remove(A key) { synchronized(data) {
    fullSize -= l(this.getOpt(key));
    data.remove(key);
  }}
  
  final void remove(Pair<A, B> p){ removePair(p); }
void removePair(Pair<A, B> p) {
    if (p != null) remove(p.a, p.b);
  }

  void remove(A key, B value) { synchronized(data) {
    List<B> list = data.get(key);
    if (list != null) {
      if (list.remove(value))
        fullSize--;
      if (list.isEmpty())
        data.remove(key);
    }
  }}

  void clear() { synchronized(data) {
    data.clear();
  }}

  boolean containsKey(A key) { synchronized(data) {
    return data.containsKey(key);
  }}

  B getFirst(A key) { synchronized(data) {
    List<B> list = get(key);
    return list.isEmpty() ? null : list.get(0);
  }}
  
  void addAll(MultiMap<A, B> map) { putAll(map); }
  
  void putAll(MultiMap<A, B> map) { synchronized(data) {
    for (A key : map.keySet())
      putAll(key, map.get(key));
  }}
  
  void putAll(Map<A, B> map) { synchronized(data) {
    if (map != null) for (Map.Entry<A, B> e : map.entrySet())
      put(e.getKey(), e.getValue());
  }}
  
  final public int keyCount(){ return keysSize(); }
public int keysSize() { synchronized(data) { return l(data); }}
  
  // full size - note: expensive operation
  final public int fullSize(){ return size(); }
public int size() { synchronized(data) {
    return fullSize;
  }}
  
  // expensive operation
  List<A> reverseGet(B b) { synchronized(data) {
    List<A> l = new ArrayList();
    for (A key : data.keySet())
      if (data.get(key).contains(b))
        l.add(key);
    return l;
  }}
  
  Map<A, List<B>> asMap() { synchronized(data) {
    return cloneMap(data);
  }}
  
  boolean isEmpty() { synchronized(data) { return data.isEmpty(); }}
  
  // override in subclasses
  List<B> _makeEmptyList() {
    return new ArrayList();
  }
  
  // returns live lists
  Collection<List<B>> allLists() {
    synchronized(data) {
      return new ArrayList(data.values());
    }
  }
  Collection<List<B>> values() { return allLists(); }
  
  List<B> allValues() {
    return concatLists(data.values());
  }
  
  Object mutex() { return data; }
  
  public String toString() { return "mm" + str(data); }
}
/*
 * @(#)WeakHashMap.java 1.5 98/09/30
 *
 * Copyright 1998 by Sun Microsystems, Inc.,
 * 901 San Antonio Road, Palo Alto, California, 94303, U.S.A.
 * All rights reserved.
 *
 * This software is the confidential and proprietary information
 * of Sun Microsystems, Inc. ("Confidential Information").  You
 * shall not disclose such Confidential Information and shall use
 * it only in accordance with the terms of the license agreement
 * you entered into with Sun.
 */
 
// From https://github.com/mernst/plume-lib/blob/df0bfafc3c16848d88f4ea0ef3c8bf3367ae085e/java/src/plume/WeakHasherMap.java

static final class WeakHasherMap<K,V> extends AbstractMap<K,V> implements Map<K,V> {

    private Hasher hasher = null;
    /*@Pure*/
    private boolean keyEquals(Object k1, Object k2) {
  return (hasher==null ? k1.equals(k2)
           : hasher.equals(k1, k2));
    }
    /*@Pure*/
    private int keyHashCode(Object k1) {
  return (hasher==null ? k1.hashCode()
           : hasher.hashCode(k1));
    }

    // The WeakKey class can't be static because it depends on the hasher.
    // That in turn means that its methods can't be static.
    // However, I need to be able to call the methods such as create() that
    // were static in the original version of this code.
    // This finesses that.

    private /*@Nullable*/ WeakKey WeakKeyCreate(K k) {
  if (k == null) return null;
  else return new WeakKey(k);
    }
    private /*@Nullable*/ WeakKey WeakKeyCreate(K k, ReferenceQueue<? super K> q) {
  if (k == null) return null;
  else return new WeakKey(k, q);
    }

    // Cannot be a static class: uses keyHashCode() and keyEquals()
    private final class WeakKey extends WeakReference<K> {
  private int hash; /* Hashcode of key, stored here since the key
           may be tossed by the GC */

  private WeakKey(K k) {
      super(k);
      hash = keyHashCode(k);
  }

  private /*@Nullable*/ WeakKey create(K k) {
      if (k == null) return null;
      else return new WeakKey(k);
  }

  private WeakKey(K k, ReferenceQueue<? super K> q) {
      super(k, q);
      hash = keyHashCode(k);
  }

  private /*@Nullable*/ WeakKey create(K k, ReferenceQueue<? super K> q) {
      if (k == null) return null;
      else return new WeakKey(k, q);
  }

        /* A WeakKey is equal to another WeakKey iff they both refer to objects
     that are, in turn, equal according to their own equals methods */
  /*@Pure*/
  @Override
  public boolean equals(/*@Nullable*/ Object o) {
            if (o == null) return false; // never happens
      if (this == o) return true;
            // This test is illegal because WeakKey is a generic type,
            // so use the getClass hack below instead.
      // if (!(o instanceof WeakKey)) return false;
            if (!(o.getClass().equals(WeakKey.class))) return false;
      Object t = this.get();
            @SuppressWarnings("unchecked")
      Object u = ((WeakKey)o).get();
      if ((t == null) || (u == null)) return false;
      if (t == u) return true;
      return keyEquals(t, u);
  }

  /*@Pure*/
  @Override
  public int hashCode() {
      return hash;
  }

    }


    /* Hash table mapping WeakKeys to values */
    private HashMap<WeakKey,V> hash;

    /* Reference queue for cleared WeakKeys */
    private ReferenceQueue<? super K> queue = new ReferenceQueue<K>();


    /* Remove all invalidated entries from the map, that is, remove all entries
       whose keys have been discarded.  This method should be invoked once by
       each public mutator in this class.  We don't invoke this method in
       public accessors because that can lead to surprising
       ConcurrentModificationExceptions. */
    @SuppressWarnings("unchecked")
    private void processQueue() {
  WeakKey wk;
  while ((wk = (WeakKey)queue.poll()) != null) { // unchecked cast
      hash.remove(wk);
  }
    }


    /* -- Constructors -- */

    /**
     * Constructs a new, empty <code>WeakHashMap</code> with the given
     * initial capacity and the given load factor.
     *
     * @param  initialCapacity  the initial capacity of the
     *                          <code>WeakHashMap</code>
     *
     * @param  loadFactor       the load factor of the <code>WeakHashMap</code>
     *
     * @throws IllegalArgumentException  If the initial capacity is less than
     *                                   zero, or if the load factor is
     *                                   nonpositive
     */
    public WeakHasherMap(int initialCapacity, float loadFactor) {
  hash = new HashMap<WeakKey,V>(initialCapacity, loadFactor);
    }

    /**
     * Constructs a new, empty <code>WeakHashMap</code> with the given
     * initial capacity and the default load factor, which is
     * <code>0.75</code>.
     *
     * @param  initialCapacity  the initial capacity of the
     *                          <code>WeakHashMap</code>
     *
     * @throws IllegalArgumentException  If the initial capacity is less than
     *                                   zero
     */
    public WeakHasherMap(int initialCapacity) {
  hash = new HashMap<WeakKey,V>(initialCapacity);
    }

    /**
     * Constructs a new, empty <code>WeakHashMap</code> with the default
     * capacity and the default load factor, which is <code>0.75</code>.
     */
    public WeakHasherMap() {
  hash = new HashMap<WeakKey,V>();
    }

    /**
     * Constructs a new, empty <code>WeakHashMap</code> with the default
     * capacity and the default load factor, which is <code>0.75</code>.
     * The <code>WeakHashMap</code> uses the specified hasher for hashing
     * keys and comparing them for equality.
     * @param h the Hasher to use when hashing values for this map
     */
    public WeakHasherMap(Hasher h) {
  hash = new HashMap<WeakKey,V>();
  hasher = h;
    }


    /* -- Simple queries -- */

    /**
     * Returns the number of key-value mappings in this map.
     * <strong>Note:</strong> <em>In contrast to most implementations of the
     * <code>Map</code> interface, the time required by this operation is
     * linear in the size of the map.</em>
     */
    /*@Pure*/
    @Override
    public int size() {
  return entrySet().size();
    }

    /**
     * Returns <code>true</code> if this map contains no key-value mappings.
     */
    /*@Pure*/
    @Override
    public boolean isEmpty() {
  return entrySet().isEmpty();
    }

    /**
     * Returns <code>true</code> if this map contains a mapping for the
     * specified key.
     *
     * @param   key   the key whose presence in this map is to be tested
     */
    /*@Pure*/
    @Override
    public boolean containsKey(Object key) {
        @SuppressWarnings("unchecked")
        K kkey = (K) key;
  return hash.containsKey(WeakKeyCreate(kkey));
    }


    /* -- Lookup and modification operations -- */

    /**
     * Returns the value to which this map maps the specified <code>key</code>.
     * If this map does not contain a value for this key, then return
     * <code>null</code>.
     *
     * @param  key  the key whose associated value, if any, is to be returned
     */
    /*@Pure*/
    @Override
    public /*@Nullable*/ V get(Object key) {  // type of argument is Object, not K
        @SuppressWarnings("unchecked")
        K kkey = (K) key;
  return hash.get(WeakKeyCreate(kkey));
    }

    /**
     * Updates this map so that the given <code>key</code> maps to the given
     * <code>value</code>.  If the map previously contained a mapping for
     * <code>key</code> then that mapping is replaced and the previous value is
     * returned.
     *
     * @param  key    the key that is to be mapped to the given
     *                <code>value</code>
     * @param  value  the value to which the given <code>key</code> is to be
     *                mapped
     *
     * @return  the previous value to which this key was mapped, or
     *          <code>null</code> if if there was no mapping for the key
     */
    @Override
    public V put(K key, V value) {
  processQueue();
  return hash.put(WeakKeyCreate(key, queue), value);
    }

    /**
     * Removes the mapping for the given <code>key</code> from this map, if
     * present.
     *
     * @param  key  the key whose mapping is to be removed
     *
     * @return  the value to which this key was mapped, or <code>null</code> if
     *          there was no mapping for the key
     */
    @Override
    public V remove(Object key) { // type of argument is Object, not K
  processQueue();
        @SuppressWarnings("unchecked")
        K kkey = (K) key;
  return hash.remove(WeakKeyCreate(kkey));
    }

    /**
     * Removes all mappings from this map.
     */
    @Override
    public void clear() {
  processQueue();
  hash.clear();
    }


    /* -- Views -- */


    /* Internal class for entries */
    // This can't be static, again because of dependence on hasher.
    @SuppressWarnings("TypeParameterShadowing")
    private final class Entry<K,V> implements Map.Entry<K,V> {
  private Map.Entry<WeakKey,V> ent;
  private K key;  /* Strong reference to key, so that the GC
           will leave it alone as long as this Entry
           exists */

  Entry(Map.Entry<WeakKey,V> ent, K key) {
      this.ent = ent;
      this.key = key;
  }

  /*@Pure*/
  @Override
  public K getKey() {
      return key;
  }

  /*@Pure*/
  @Override
  public V getValue() {
      return ent.getValue();
  }

  @Override
  public V setValue(V value) {
      return ent.setValue(value);
  }

        /*@Pure*/
        private boolean keyvalEquals(K o1, K o2) {
      return (o1 == null) ? (o2 == null) : keyEquals(o1, o2);
  }

        /*@Pure*/
        private boolean valEquals(V o1, V o2) {
      return (o1 == null) ? (o2 == null) : o1.equals(o2);
  }

        /*@Pure*/
        @SuppressWarnings("NonOverridingEquals")
        public boolean equals(Map.Entry<K,V> e /* Object o*/) {
            // if (! (o instanceof Map.Entry)) return false;
            // Map.Entry<K,V> e = (Map.Entry<K,V>)o;
      return (keyvalEquals(key, e.getKey())
        && valEquals(getValue(), e.getValue()));
  }

  /*@Pure*/
  @Override
  public int hashCode() {
      V v;
      return (((key == null) ? 0 : keyHashCode(key))
        ^ (((v = getValue()) == null) ? 0 : v.hashCode()));
  }

    }


    /* Internal class for entry sets */
    private final class EntrySet extends AbstractSet<Map.Entry<K,V>> {
  Set<Map.Entry<WeakKey,V>> hashEntrySet = hash.entrySet();

  @Override
  public Iterator<Map.Entry<K,V>> iterator() {

      return new Iterator<Map.Entry<K,V>>() {
    Iterator<Map.Entry<WeakKey,V>> hashIterator = hashEntrySet.iterator();
    Map.Entry<K,V> next = null;

    @Override
    public boolean hasNext() {
        while (hashIterator.hasNext()) {
      Map.Entry<WeakKey,V> ent = hashIterator.next();
      WeakKey wk = ent.getKey();
      K k = null;
      if ((wk != null) && ((k = wk.get()) == null)) {
          /* Weak key has been cleared by GC */
          continue;
      }
      next = new Entry<K,V>(ent, k);
      return true;
        }
        return false;
    }

    @Override
    public Map.Entry<K,V> next() {
        if ((next == null) && !hasNext())
      throw new NoSuchElementException();
        Map.Entry<K,V> e = next;
        next = null;
        return e;
    }

    @Override
    public void remove() {
        hashIterator.remove();
    }

      };
  }

  /*@Pure*/
  @Override
  public boolean isEmpty() {
      return !(iterator().hasNext());
  }

  /*@Pure*/
  @Override
  public int size() {
      int j = 0;
      for (Iterator<Map.Entry<K,V>> i = iterator(); i.hasNext(); i.next()) j++;
      return j;
  }

  @Override
  public boolean remove(Object o) {
      processQueue();
      if (!(o instanceof Map.Entry<?,?>)) return false;
            @SuppressWarnings("unchecked")
      Map.Entry<K,V> e = (Map.Entry<K,V>)o; // unchecked cast
      Object ev = e.getValue();
      WeakKey wk = WeakKeyCreate(e.getKey());
      Object hv = hash.get(wk);
      if ((hv == null)
    ? ((ev == null) && hash.containsKey(wk)) : hv.equals(ev)) {
    hash.remove(wk);
    return true;
      }
      return false;
  }

  /*@Pure*/
  @Override
  public int hashCode() {
      int h = 0;
      for (Iterator<Map.Entry<WeakKey,V>> i = hashEntrySet.iterator(); i.hasNext(); ) {
    Map.Entry<WeakKey,V> ent = i.next();
    WeakKey wk = ent.getKey();
    Object v;
    if (wk == null) continue;
    h += (wk.hashCode()
          ^ (((v = ent.getValue()) == null) ? 0 : v.hashCode()));
      }
      return h;
  }

    }


    private /*@Nullable*/ Set<Map.Entry<K,V>> entrySet = null;

    /**
     * Returns a <code>Set</code> view of the mappings in this map.
     */
    /*@SideEffectFree*/
    @Override
    public Set<Map.Entry<K,V>> entrySet() {
  if (entrySet == null) entrySet = new EntrySet();
  return entrySet;
    }

    // find matching key
    K findKey(Object key) {
      processQueue();
      K kkey = (K) key;
      // TODO: use replacement for HashMap to avoid reflection
      WeakKey wkey = WeakKeyCreate(kkey);
      WeakKey found = hashMap_findKey(hash, wkey);
      return found == null ? null : found.get();
    }
}
static interface Steppable {
  public boolean step(); // return false if done
}
static class Pair<A, B> implements Comparable<Pair<A, B>> {
  A a;
  B b;

  Pair() {}
  Pair(A a, B b) {
  this.b = b;
  this.a = a;}
  
  public int hashCode() {
    return hashCodeFor(a) + 2*hashCodeFor(b);
  }
  
  public boolean equals(Object o) {
    if (o == this) return true;
    if (!(o instanceof Pair)) return false;
    Pair t = (Pair) o;
    return eq(a, t.a) && eq(b, t.b);
  }
  
  public String toString() {
    return "<" + a + ", " + b + ">";
  }
  
  public int compareTo(Pair<A, B> p) {
    if (p == null) return 1;
    int i = ((Comparable<A>) a).compareTo(p.a);
    if (i != 0) return i;
    return ((Comparable<B>) b).compareTo(p.b);
  }
}
static class Fail extends RuntimeException implements IFieldsToList{
  Object[] objects;
  Fail() {}
  Fail(Object... objects) {
  this.objects = objects;}public Object[] _fieldsToList() { return new Object[] {objects}; }

  Fail(Throwable cause, Object... objects) {
    super(cause);
  this.objects = objects;
  }
  
  public String toString() { return joinNemptiesWithColon("Fail", commaCombine(getCause(), objects)); }
}
final static class Rect implements IFieldsToList{
  static final String _fieldOrder = "x y w h";
  int x;
  int y;
  int w;
  int h;
  Rect() {}
  Rect(int x, int y, int w, int h) {
  this.h = h;
  this.w = w;
  this.y = y;
  this.x = x;}

public boolean equals(Object o) {
if (!(o instanceof Rect)) return false;
    Rect __1 =  (Rect) o;
    return x == __1.x && y == __1.y && w == __1.w && h == __1.h;
}

  public int hashCode() {
    int h = 2543108;
    h = boostHashCombine(h, _hashCode(x));
    h = boostHashCombine(h, _hashCode(y));
    h = boostHashCombine(h, _hashCode(w));
    h = boostHashCombine(h, _hashCode(h));
    return h;
  }
  public Object[] _fieldsToList() { return new Object[] {x, y, w, h}; }

  Rect(Rectangle r) {
    x = r.x;
    y = r.y;
    w = r.width;
    h = r.height;
  }
  
  Rect(Pt p, int w, int h) {
  this.h = h;
  this.w = w; x = p.x; y = p.y; }
  Rect(Rect r) { x = r.x; y = r.y; w = r.w; h = r.h; }
  
  Rectangle getRectangle() {
    return new Rectangle(x, y, w, h);
  }
  
  public String toString() {
    return x + "," + y + " / " + w + "," + h;
  }
  
  int x1() { return x; }
  int y1() { return y; }
  int x2() { return x + w; }
  int y2() { return y + h; }
  
  boolean contains(Pt p) {
    return contains(p.x, p.y);
  }
  
  boolean contains(int _x, int _y) {
    return _x >= x && _y >= y && _x < x+w && _y < y+h;
  }
  
  boolean contains(Rectangle r) {
    return rectContains(this, r);
  }
  
  boolean empty() { return w <= 0 || h <= 0; }
  
  int getWidth() { return w; }
  int getHeight() { return h; }
}
static class Pt implements Comparable<Pt>, IDoublePt {
  int x, y;
  
  Pt() {}
  Pt(Point p) {
    x = p.x;
    y = p.y;
  }
  Pt(int x, int y) {
  this.y = y;
  this.x = x;}
  
  Point getPoint() {
    return new Point(x, y);
  }
  
  public boolean equals(Object o) {
    return o instanceof Pt && x == ((Pt) o).x && y == ((Pt) o).y;
  }
  
  public int hashCode() {
    return boostHashCombine(x, y);
  }
  
  // compare in scan order
  public int compareTo(Pt p) {
    if (y != p.y) return cmp(y, p.y);
    return cmp(x, p.x);
  }
  
  public String toString() {
    return x + ", " + y;
  }
  
  double length() { return sqrt(x*x+y*y); }
  
  public Pt minus(Pt p) { return ptMinus(this, p); }
  
  public double x_double() { return x; }
  public double y_double() { return y; }
}
static abstract class F0<A> {
  abstract A get();
}
static abstract class F1<A, B> {
  abstract B get(A a);
}
// you still need to implement hasNext() and next()
static abstract class IterableIterator<A> implements Iterator<A>, Iterable<A> {
  public Iterator<A> iterator() {
    return this;
  }
  
  public void remove() {
    unsupportedOperation();
  }
}
public static interface IF0<A> {
  A get();
}
static interface Hasher<A> {
  int hashCode(A a);
  boolean equals(A a, A b);
}

static interface IFieldsToList {
  Object[] _fieldsToList();
}
static interface IF2<A, B, C> {
  C get(A a, B b);
}
static class PtBuffer extends RandomAccessAbstractList  < Pt > {
  LongBuffer buf = new LongBuffer();
  
  PtBuffer() {}
  PtBuffer(int size) { buf.allocate(size); }
  
  PtBuffer(Iterable<Pt> l) {
    if (l != null) for (Pt p : l) add(p);
  }
  
  public int size() { return buf.size(); }
  
  public Pt get(int i) {
    return longToPt(buf.get(i));
  }
  
  public Pt set(int i, Pt val) {
    Pt old = get(i);
    buf.set(i, ptToLong(val));
    return old;
  }
  
  public boolean add(Pt p) {
    buf.add(ptToLong(p));
    return true;
  }
  
  public void add(int x, int y) {
    buf.add(ptToLong(x, y));
  }
  
  public Pt remove(int i) {
    Pt p = get(i);
    buf.remove(i);
    return p;
  }
  
  public void clear() { buf.clear(); }
}
static interface IF1<A, B> {
  B get(A a);
}
static class PersistableThrowable extends DynamicObject {
  String className;
  String msg;
  String stacktrace;
  
  PersistableThrowable() {}
  PersistableThrowable(Throwable e) {
    if (e == null)
      className = "Crazy Null Error";
    else {
      className = getClassName(e).replace('/', '.');
      msg = e.getMessage();
      stacktrace = getStackTrace_noRecord(e);
    }
  }
  
  public String toString() {
    return nempty(msg) ? className + ": " + msg : className;
  }
  
  RuntimeException asRuntimeException() {
    return new Fail(this);
  }
}
static interface IVF1<A> {
  void get(A a);
}
static interface WidthAndHeight {
  default int w(){ return getWidth(); }
int getWidth();
  default int h(){ return getHeight(); }
int getHeight();
  
  public default Rect bounds() { return rect(0, 0, getWidth(), getHeight()); }
}


/*
 * #!
 * Ontopia Engine
 * #-
 * Copyright (C) 2001 - 2013 The Ontopia Project
 * #-
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 * 
 *      http://www.apache.org/licenses/LICENSE-2.0
 * 
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 * !#
 */

// modified by Stefan Reich

// a compact unordered set of longs. unsynchronized

static class CompactLongSet extends java.util.AbstractSet<Long> {
  protected final static int INITIAL_SIZE = 3;
  public final static double LOAD_FACTOR = 0.75;

  protected final static long deletedObject = Long.MIN_VALUE;
  
  boolean containsZero, containsDeletedObject; // special handling for sentinels
  protected int elements;
  protected int freecells;
  protected long[] objects;
  
  
  protected int modCount;
  
  
  CompactLongSet() { this(0); }

  // This applies the load factor so the set should be able to hold
  // expectedElements without growing (haven't tested if this works exactly).
  CompactLongSet(int expectedElements) {
    int size = max(INITIAL_SIZE, iceil(expectedElements/LOAD_FACTOR));
    // NOTE: If array size is 0, we get a
    // "java.lang.ArithmeticException: / by zero" in add(Object).
    objects = new long[size];
    freecells = objects.length;
  }

  CompactLongSet(Collection<Long> c) {
    this(c.size());
    addAll(c);
  }

  @Override
  public RenamedLongIterator iterator() {
    return new CompactHashIterator();
  }

  @Override
  public int size() {
    return elements;
  }

  @Override
  public boolean isEmpty() {
    return elements == 0;
  }

  @Override
  public boolean contains(Object o) {
    return contains((long) o);
  }
  
  public boolean contains(long o) {
    if (o == 0) return containsZero;
    if (o == deletedObject) return containsDeletedObject;

    int hash = hash(o);
    int index = (hash & 0x7FFFFFFF) % objects.length;
    int offset = 1;

    // search for the object (continue while !null and !this object)
    while (objects[index] != 0) {
      if (objects[index] == o) return true;
      index = ((index + offset) & 0x7FFFFFFF) % objects.length;
      offset = offset*2 + 1;

      if (offset == -1)
        offset = 2;
    }

    return false;
  }
  
  @Override
  public boolean add(Long o) {
    return add((long) o);
  }
  
  public boolean add(long o) {
    if (o == 0) {
      if (containsZero) return false;
      containsZero = true; elements++; return true;
    }
    if (o == deletedObject)  {
      if (containsDeletedObject) return false;
      containsDeletedObject = true; elements++; return true;
    }
    int hash = hash(o);
    int index = (hash & 0x7FFFFFFF) % objects.length;
    int offset = 1;
    int deletedix = -1;
    
    // search for the object (continue while !null and !this object)
    while (objects[index] != 0 && objects[index] != o) {

      // if there's a deleted object here we can put this object here,
      // provided it's not in here somewhere else already
      if (objects[index] == deletedObject)
        deletedix = index;
      
      index = ((index + offset) & 0x7FFFFFFF) % objects.length;
      offset = offset*2 + 1;

      if (offset == -1)
        offset = 2;
    }
    
    if (objects[index] == 0) { // wasn't present already
      if (deletedix != -1) // reusing a deleted cell
        index = deletedix;
      else
        freecells--;

      
        modCount++;
      
      elements++;

      objects[index] = o;
      
      // do we need to rehash?
      if (1 - (freecells / (double) objects.length) > LOAD_FACTOR)
        rehash();
      return true;
    } else // was there already 
      return false;
  }
  
  @Override
  public boolean remove(Object o) {
    return remove((long) o);
  }
  
  public boolean remove(long o) {
    if (o == 0) {
      if (!containsZero) return false;
      containsZero = false; --elements;
      return true;
    }
    
    if (o == deletedObject) {
      if (!containsDeletedObject) return false;
      containsDeletedObject = false; --elements;
      return true;
    }
    
    int hash = hash(o);
    int index = (hash & 0x7FFFFFFF) % objects.length;
    int offset = 1;
    
    // search for the object (continue while !null and !this object)
    while (objects[index] != 0 && objects[index] != o) {
      index = ((index + offset) & 0x7FFFFFFF) % objects.length;
      offset = offset*2 + 1;

      if (offset == -1)
        offset = 2;
    }

    // we found the right position, now do the removal
    if (objects[index] != 0) {
      // we found the object

      // same problem here as with add
      objects[index] = deletedObject;
      
        modCount++;
      
      elements--;
      return true;
    } else
      // we did not find the object
      return false;
  }
  
  @Override
  public void clear() {
    elements = 0;
    for (int ix = 0; ix < objects.length; ix++)
      objects[ix] = 0;
    containsZero = containsDeletedObject = false;
    freecells = objects.length;
    
      modCount++;
    
  }

  protected void rehash() {
    int garbagecells = objects.length - (elements + freecells);
    if (garbagecells / (double) objects.length > 0.05)
      // rehash with same size
      rehash(objects.length);
    else
      // rehash with increased capacity
      rehash(objects.length*2 + 1);
  }
  
  protected void rehash(int newCapacity) {
    int oldCapacity = objects.length;
    @SuppressWarnings("unchecked")
    long[] newObjects = new long[newCapacity];

    for (int ix = 0; ix < oldCapacity; ix++) {
      long o = objects[ix];
      if (o == 0 || o == deletedObject)
        continue;
      
      int hash = hash(o);
      int index = (hash & 0x7FFFFFFF) % newCapacity;
      int offset = 1;

      // search for the object
      while(newObjects[index] != 0) { // no need to test for duplicates
        index = ((index + offset) & 0x7FFFFFFF) % newCapacity;
        offset = offset*2 + 1;

        if (offset == -1)
          offset = 2;
      }

      newObjects[index] = o;
    }

    objects = newObjects;
    freecells = objects.length - elements;
  }
  
  private class CompactHashIterator extends RenamedLongIterator {
    private int index;
    private int lastReturned = -1;
    boolean sendZero, sendDeletedObject;

    
      private int expectedModCount;
    

    @SuppressWarnings("empty-statement")
    public CompactHashIterator() {
      // find first non-empty slot
      for (index = 0; index < objects.length &&
                      (objects[index] == 0 ||
                      objects[index] == deletedObject); index++)
        ;
      
        expectedModCount = modCount;
      
      
      sendZero = containsZero;
      sendDeletedObject = containsDeletedObject;
    }

    @Override
    public boolean hasNext() {
      return index < objects.length || sendZero || sendDeletedObject;
    }

    @Override
    public long nextLong() {
      /*if (modCount != expectedModCount)
        throw new ConcurrentModificationException();*/
      int length = objects.length;
      
      if (index >= length) {
        if (sendZero) { sendZero = false; return 0L; }
        if (sendDeletedObject) { sendDeletedObject = false; return deletedObject; }
        throw new NoSuchElementException();
      }

      lastReturned = index;
      for (index += 1; index < length &&
                       (objects[index] == 0 ||
                        objects[index] == deletedObject); index++)
        ;

      return objects[lastReturned];
    }

    @Override
    public void remove() {
        
          if (modCount != expectedModCount)
            throw new ConcurrentModificationException();
        
        if (lastReturned == -1 || lastReturned == -2)
          throw new IllegalStateException();
        // delete object
        if (objects[lastReturned] != 0 && objects[lastReturned] != deletedObject) {
          objects[lastReturned] = deletedObject;
          elements--;
          
            modCount++;
            expectedModCount = modCount; // this is expected; we made the change
          
        }
    }
  }
  
  int capacity() { return objects.length; }
  
  // returns true if there was a shrink
  boolean shrinkToFactor(double factor) {
    if (factor > LOAD_FACTOR)
      throw fail("Shrink factor must be equal to or smaller than load factor: " + factor + " / " + LOAD_FACTOR);
    int newCapacity = max(INITIAL_SIZE, iround(size()/factor));
    if (newCapacity >= capacity()) return false;
    rehash(newCapacity);
    return true;
  }
  
  int hash(long l) { return main.hashCode(l); }
}
static class LongBuffer implements Iterable<Long>, ILongQueue {
  long[] data;
  int size;
  
  LongBuffer() {}
  LongBuffer(int size) { if (size != 0) data = new long[size]; }
  LongBuffer(Iterable<Long> l) {
    if (l instanceof Collection) allocate(((Collection) l).size());
    addAll(l);
  }
  
  public void add(long i) {
    if (size >= lLongArray(data)) {
      data = resizeLongArray(data, Math.max(1, toInt(Math.min(maximumSafeArraySize(), lLongArray(data)*2L))));
      if (size >= data.length) throw fail("LongBuffer too large: " + size);
    }
    data[size++] = i;
  }
  
  void allocate(int n) {
    data = resizeLongArray(data, max(n, size()));
  }
  
  void addAll(Iterable<Long> l) {
    if (l != null) for (long i : l) add(i);
  }
  
  long[] toArray() {
    return size == 0 ? null : resizeLongArray(data, size);
  }
  
  List<Long> toList() {
    return longArrayToList(data, 0, size);
  }
  
  List<Long> asVirtualList() {
    return listFromFunction(__31 -> get(__31), size);
  }
  
  void reset() { size = 0; }
  void clear() { reset(); }
  
  int size() { return size; }
  public boolean isEmpty() { return size == 0; }
  
  long get(int idx) {
    if (idx >= size) throw fail("Index out of range: " + idx + "/" + size);
    return data[idx];
  }
  
  void set(int idx, long value) {
    if (idx >= size) throw fail("Index out of range: " + idx + "/" + size);
    data[idx] = value;
  }
  
  long popLast() {
    if (size == 0) throw fail("empty buffer");
    return data[--size];
  }
  
  long last() { return data[size-1]; }
  long nextToLast() { return data[size-2]; }
  
  public String toString() { return squareBracket(joinWithSpace(toList())); }
  
  public Iterator<Long> iterator() {
    return new IterableIterator<Long>() {
      int i = 0;
      
      public boolean hasNext() { return i < size; }
      public Long next() {
        if (!hasNext()) throw fail("Index out of bounds: " + i);
        return data[i++];
      }
    };
  }
  
  void trimToSize() {
    data = resizeLongArray(data, size);
  }
  
  void remove(int idx) {
    arraycopy(data, idx+1, data, idx, size-1-idx);
    --size;
  }
  
  // don't rely on return value if buffer is empty
  public long poll() { 
    return size == 0 ? -1 : data[--size];
  }
}
abstract static class RenamedLongIterator extends IterableIterator<Long> {
  abstract long nextLong();
  
  @Override
  public Long next() { return nextLong(); }
}
static class OnePathWithOrigin extends OnePath {
   final public OnePathWithOrigin setOrigin(Pt origin){ return origin(origin); }
public OnePathWithOrigin origin(Pt origin) { this.origin = origin; return this; }  final public Pt getOrigin(){ return origin(); }
public Pt origin() { return origin; }
 Pt origin = pt(0, 0);
  
  OnePathWithOrigin() {}
  OnePathWithOrigin(String path) { super(path); }
  OnePathWithOrigin(Pt origin, String path) { super(path);
  this.origin = origin; }
  OnePathWithOrigin(int originX, int originY, String path) { super(path); origin = pt(originX, originY); }
  OnePathWithOrigin(Iterable<Pt> points, boolean close) {
    var l = asList(points);
    origin = first(l);
    fromPoints(l, close);
  }
  
  public String toString() {
    return "Origin (" + origin + "), path: " + super.toString();
  }
}
static interface ISetter<A> {
 void set(A a);
}

interface IMultiMap<A, B> {
  public Set<A> keySet();
  public Collection<B> get(A a);
  public int size();
  public int keyCount();
}
interface IDoublePt {
  public double x_double();
  public double y_double();
}
abstract static class RandomAccessAbstractList<A> extends AbstractList<A> implements RandomAccess {
}
static class RGB {
  // usually in range [0, 1]
  public float r, g, b; // can't be final cause persistence
  
  RGB() {}
  
  public RGB(float r, float g, float b) {
    this.r = r;
    this.g = g;
    this.b = b;
  }

  public RGB(double r, double g, double b) {
    this.r = (float) r;
    this.g = (float) g;
    this.b = (float) b;
  }
  
  public RGB(double[] rgb) {
    this(rgb[0], rgb[1], rgb[2]);
  }

  public RGB(int rgb) {
    this(new Color(rgb));
  }
  
  public RGB(double brightness) {
    this.r = this.g = this.b = max(0f, min(1f, (float) brightness));
  }

  public RGB(Color color) {
    this.r = color.getRed()/255f;
    this.g = color.getGreen()/255f;
    this.b = color.getBlue()/255f;
  }

  // TODO: 3-char version
  public RGB(String hex) {
    int i = l(hex)-6;
    r = Integer.parseInt(hex.substring(i, i+2), 16)/255f;
    g = Integer.parseInt(hex.substring(i+2, i+4), 16)/255f;
    b = Integer.parseInt(hex.substring(i+4, i+6), 16)/255f;
  }

  public float getComponent(int i) {
    return i == 0 ? r : i == 1 ? g : b;
  }

  public int getInt(int i) {
    return i == 0 ? redInt() : i == 1 ? greenInt() : blueInt();
  }
  
  public Color getColor() {
    return new Color(r, g, b);
  }

  public static RGB newSafe(float r, float g, float b) {
    return new RGB(Math.max(0, Math.min(1, r)), Math.max(0, Math.min(1, g)), Math.max(0, Math.min(1, b)));
  }

  int asInt() { return getColor().getRGB() & 0xFFFFFF; }
  int getInt() { return getColor().getRGB() & 0xFFFFFF; }
  int asIntWithAlpha() { return rgbInt(redInt(), greenInt(), blueInt()) | 0xFF000000; }

  public float getBrightness() {
    return (r+g+b)/3.0f;
  }

  public String getHexString() {
    return Integer.toHexString(asInt() | 0xFF000000).substring(2).toUpperCase();
  }

  @Override
  public boolean equals(Object o) {
    if (this == o) return true;
    if (!(o instanceof RGB)) return false;

    RGB rgb = (RGB) o;

    if (Float.compare(rgb.b, b) != 0) return false;
    if (Float.compare(rgb.g, g) != 0) return false;
    if (Float.compare(rgb.r, r) != 0) return false;

    return true;
  }

  @Override
  public int hashCode() {
    int result = (r != +0.0f ? Float.floatToIntBits(r) : 0);
    result = 31 * result + (g != +0.0f ? Float.floatToIntBits(g) : 0);
    result = 31 * result + (b != +0.0f ? Float.floatToIntBits(b) : 0);
    return result;
  }

  public boolean isBlack() {
    return r == 0f && g == 0f && b == 0f;
  }

  public boolean isWhite() {
    return r == 1f && g == 1f && b == 1f;
  }

  public String toString() {
    return getHexString();
  }
  
  int redInt() { return iround(r*255); }
  int greenInt() { return iround(g*255); }
  int blueInt() { return iround(b*255); }
  
  static float brightnessToFloat(int brightness) { return brightness/255f; }
}
static interface IVar<A> extends IF0<A> {
  void set(A a);
  A get();
  
  // reified type of value (if available)
  default Class<A> getType() { return null; }
  
  
  default boolean has() { return get() != null; }
  default void clear() { set(null); }
  
}


static interface ILongQueue {
  public boolean isEmpty();
  public void add(long element);
  
  // return value is undefined if queue is empty
  public long poll();
}
static class OnePath {
  ByteBuffer steps = new ByteBuffer();
  
  OnePath() {}
  OnePath(String path) {
    int n = l(path);
    steps.allocate(n);
    for (int i = 0; i < n; i++)
      steps.add(parseDigit(path, i));
  }

  // uses first point as origin, so there will be l(points)-1 steps.
  // Unless you set close to true, then it adds the first point at the end again.
  
  OnePath(Iterable<Pt> points, boolean close) {
    fromPoints(points, close);
  }
  
  void fromPoints(Iterable<Pt> points, boolean close) {
    var it = iterator(points);
    if (empty(it)) return;
    Pt firstPoint = it.next(), p = firstPoint;
    while (it.hasNext()) {
      Pt p2 = it.next();
      steps.add(ptToDigit(ptMinus(p2, p)));
      p = p2;
    }
    
    if (close)
      steps.add(ptToDigit(ptMinus(firstPoint, p)));
  }
  
  final int length(){ return size(); }
final int nSteps(){ return size(); }
int size() { return steps.size(); }
  
  public String toString() { return pathString(); }
  
  String pathString() {
    return singleDigitBytesToString(steps);
  }
  
  // includes first point, so returns length()+1 points in total
  IterableIterator<Pt> pointIterator() { return pointIterator(origin()); }
IterableIterator<Pt> pointIterator(Pt startPt) {
    return new IterableIterator<Pt>() {
      int i = 0, n = length();
      Pt p = startPt;
      
      public boolean hasNext() { return i <= n; }
      
      public Pt next() {
        var p = this.p;
        if (i < n) this.p = translatePt(this.p, getStepAsPt(i));
        ++i;
        return p;
      }
    };
  }
  
  List<Pt> pointList() { return ptBuffer(pointIterator()); }
  
  int getStep(int i) { return steps.get(i); }
  
  Pt getStepAsPt(int i) {
    return onePathDirections()[steps.get(i)];
  }
  
  static int ptToDigit(Pt p) {
    return p.y < 0 ? p.x < 0 ? 1 : p.x == 0 ? 2 : 3
      : p.y == 0 ? p.x < 0 ? 8 : p.x == 0 ? 0 : 4
      : p.x < 0 ? 7 : p.x == 0 ? 6 : 5;
  }
  
  Pt drift() {
    return ptMinus(last(pointIterator()), first(pointIterator()));
  }
  
  Pt origin() { return main.origin(); }
  
  void addStep(int p_x, int p_y) { addStep(pt(p_x, p_y)); }

void addStep(Pt p) {
    int step = onePathLookupDirection(p);
    if (step < 0) throw fail("Invalid one path step: " + p);
    addStep(step);
  }
  
  void addStep(int step) {
    assertBetween(0, 8, step);
    steps.add(step);
  }
  
  void insertStep(int idx, int p_x, int p_y) { insertStep(idx, pt(p_x, p_y)); }

void insertStep(int idx, Pt p) {
    int step = onePathLookupDirection(p);
    if (step < 0) throw fail("Invalid one path step: " + p);
    insertStep(idx, step);
  }
  
  void insertStep(int idx, int step) {
    assertBetween(0, 8, step);
    steps.add(idx, step);
  }
}


static class ByteBuffer implements Iterable<Byte> {
  byte[] data;
  int size;
  
  ByteBuffer() {}
  ByteBuffer(int size) { if (size != 0) data = new byte[size]; }
  ByteBuffer(Iterable<Byte> l) {
    if (l instanceof Collection) allocate(((Collection) l).size());
    addAll(l);
  }
  ByteBuffer(byte[] data) { this.data = data; size = l(data); }
  
  void add(int idx, int i) {
    add(0);
    arraycopy(data, idx, data, idx+1, size-(idx+1));
    data[idx] = (byte) i;
  }
  
  void add(int i) { add((byte) i); }
  
  void add(byte i) {
    if (size >= lByteArray(data)) {
      allocate(Math.max(1, toInt(Math.min(maximumSafeArraySize(), lByteArray(data)*2L))));
      if (size >= data.length) throw fail("ByteBuffer too large: " + size);
    }
    data[size++] = i;
  }
  
  void allocate(int n) {
    data = resizeByteArray(data, max(n, size()));
  }
  
  void addAll(Iterable<Byte> l) {
    if (l != null) for (byte i : l) add(i);
  }
  
  final byte[] toByteArray(){ return toArray(); }
byte[] toArray() {
    return size == 0 ? null : resizeByteArray(data, size);
  }
  
  List<Byte> toList() {
    return byteArrayToList(data, 0, size);
  }

  List<Byte> asVirtualList() {
    return new RandomAccessAbstractList<Byte>() {
      public int size() { return size; }
      public Byte get(int i) { return ByteBuffer.this.get(i); }
      public Byte set(int i, Byte val) {
        Byte a = get(i);
        data[i] = val;
        return a;
      }
    };
  }
  
  void reset() { size = 0; }
  void clear() { reset(); }
  
  int size() { return size; }
  boolean isEmpty() { return size == 0; }
  
  byte get(int idx) {
    if (idx >= size) throw fail("Index out of range: " + idx + "/" + size);
    return data[idx];
  }
  
  void set(int idx, byte value) {
    if (idx >= size) throw fail("Index out of range: " + idx + "/" + size);
    data[idx] = value;
  }
  
  byte popLast() {
    if (size == 0) throw fail("empty buffer");
    return data[--size];
  }
  
  // unefficient
  byte popFirst() {
    if (size == 0) throw fail("empty buffer");
    byte b = data[0];
    arraycopy(data, 1, 0, --size);
    return b;
  }
  
  byte last() { return data[size-1]; }
  byte nextToLast() { return data[size-2]; }
  
  public String toString() { return squareBracket(joinWithSpace(toList())); }
  
  public Iterator<Byte> iterator() {
    return new IterableIterator<Byte>() {
      int i = 0;
      
      public boolean hasNext() { return i < size; }
      public Byte next() {
        //if (!hasNext()) fail("Index out of bounds: " + i);
        return data[i++];
      }
    };
  }
  
  /*public ByteIterator byteIterator() {
    ret new ByteIterator {
      int i = 0;
      
      public bool hasNext() { ret i < size; }
      public int next() {
        //if (!hasNext()) fail("Index out of bounds: " + i);
        ret data[i++];
      }
      toString { ret "Iterator@" + i + " over " + ByteBuffer.this; }
    };
  }*/
  
  void trimToSize() {
    data = resizeByteArray(data, size);
  }
  
  int indexOf(byte b) {
    for (int i = 0; i < size; i++)
      if (data[i] == b)
        return i;
    return -1;
  }
  
  byte[] subArray(int start, int end) {
    return subByteArray(data, start, min(end, size));
  }
}


static Class<?> getClass(String name) {
  return _getClass(name);
}

static Class getClass(Object o) {
  return _getClass(o);
}

static Class getClass(Object realm, String name) {
  return _getClass(realm, name);
}


static boolean classIsExportedTo(Class c, java.lang.Module destModule) {
  if (c == null || destModule == null) return false;
  
  java.lang.Module srcModule = c.getModule();
  String packageName = c.getPackageName();
  return srcModule.isExported(packageName, destModule);
}


static boolean isAbstract(Class c) {
  return (c.getModifiers() & Modifier.ABSTRACT) != 0;
}

static boolean isAbstract(Method m) {
  return (m.getModifiers() & Modifier.ABSTRACT) != 0;
}


static boolean reflection_isForbiddenMethod(Method m) {
  return m.getDeclaringClass() == Object.class
    && eqOneOf(m.getName(), "finalize", "clone", "registerNatives");
}


static Set<Class> allInterfacesImplementedBy(Class c) {
  if (c == null) return null;
  HashSet<Class> set = new HashSet();
  allInterfacesImplementedBy_find(c, set);
  return set;
}

static void allInterfacesImplementedBy_find(Class c, Set<Class> set) {
  if (c.isInterface() && !set.add(c)) return;
  do {
    for (Class intf : c.getInterfaces())
      allInterfacesImplementedBy_find(intf, set);
  } while ((c = c.getSuperclass()) != null);
}


static Method findMethod(Object o, String method, Object... args) {
  return findMethod_cached(o, method, args);
}

static boolean findMethod_checkArgs(Method m, Object[] args, boolean debug) {
  Class<?>[] types = m.getParameterTypes();
  if (types.length != args.length) {
    if (debug)
      System.out.println("Bad parameter length: " + args.length + " vs " + types.length);
    return false;
  }
  for (int i = 0; i < types.length; i++)
    if (!(args[i] == null || isInstanceX(types[i], args[i]))) {
      if (debug)
        System.out.println("Bad parameter " + i + ": " + args[i] + " vs " + types[i]);
      return false;
    }
  return true;
}


static Method findStaticMethod(Class c, String method, Object... args) {
  Class _c = c;
  while (c != null) {
    for (Method m : c.getDeclaredMethods()) {
      if (!m.getName().equals(method))
        continue;

      if ((m.getModifiers() & Modifier.STATIC) == 0 || !findStaticMethod_checkArgs(m, args))
        continue;

      return m;
    }
    c = c.getSuperclass();
  }
  return null;
}

static boolean findStaticMethod_checkArgs(Method m, Object[] args) {
  Class<?>[] types = m.getParameterTypes();
  if (types.length != args.length)
    return false;
  for (int i = 0; i < types.length; i++)
    if (!(args[i] == null || isInstanceX(types[i], args[i])))
      return false;
  return true;
}



static void add(BitSet bs, int i) {
  bs.set(i);
}

static <A> boolean add(Collection<A> c, A a) {
  return c != null && c.add(a);
}


static void add(Container c, Component x) {
  addToContainer(c, x);
}


static long add(AtomicLong l, long b) {
  return l.addAndGet(b);
}


static long ptToLong(Pt p) {
  return p == null ? -1: intPairToLong(p.x, p.y);
}

static long ptToLong(int x, int y) {
  return intPairToLong(x, y);
}


static Pt ptFromLong(long l) {
  return longToPt(l);
}


static String unquote(String s) {
  if (s == null) return null;
  if (startsWith(s, '[')) {
    int i = 1;
    while (i < s.length() && s.charAt(i) == '=') ++i;
    if (i < s.length() && s.charAt(i) == '[') {
      String m = s.substring(1, i);
      if (s.endsWith("]" + m + "]"))
        return s.substring(i+1, s.length()-i-1);
    }
  }
  
  if (s.length() > 1) {
    char c = s.charAt(0);
    if (c == '\"' || c == '\'') {
      int l = endsWith(s, c) ? s.length()-1 : s.length();
      StringBuilder sb = new StringBuilder(l-1);
  
      for (int i = 1; i < l; i++) {
        char ch = s.charAt(i);
        if (ch == '\\') {
          char nextChar = (i == l - 1) ? '\\' : s.charAt(i + 1);
          // Octal escape?
          if (nextChar >= '0' && nextChar <= '7') {
              String code = "" + nextChar;
              i++;
              if ((i < l - 1) && s.charAt(i + 1) >= '0'
                      && s.charAt(i + 1) <= '7') {
                  code += s.charAt(i + 1);
                  i++;
                  if ((i < l - 1) && s.charAt(i + 1) >= '0'
                          && s.charAt(i + 1) <= '7') {
                      code += s.charAt(i + 1);
                      i++;
                  }
              }
              sb.append((char) Integer.parseInt(code, 8));
              continue;
          }
          switch (nextChar) {
          case '\"': ch = '\"'; break;
          case '\\': ch = '\\'; break;
          case 'b': ch = '\b'; break;
          case 'f': ch = '\f'; break;
          case 'n': ch = '\n'; break;
          case 'r': ch = '\r'; break;
          case 't': ch = '\t'; break;
          case '\'': ch = '\''; break;
          // Hex Unicode: u????
          case 'u':
              if (i >= l - 5) {
                  ch = 'u';
                  break;
              }
              int code = Integer.parseInt(
                      "" + s.charAt(i + 2) + s.charAt(i + 3)
                         + s.charAt(i + 4) + s.charAt(i + 5), 16);
              sb.append(Character.toChars(code));
              i += 5;
              continue;
          default:
            ch = nextChar; // added by Stefan
          }
          i++;
        }
        sb.append(ch);
      }
      return sb.toString();
    }
  }
    
  return s; // not quoted - return original
}


static List<String> quoteAll(String[] l) {
  return quoteAll(asList(l));
}

static List<String> quoteAll(Collection<String> l) {
  List<String> x = new ArrayList();
  for (String s : l)
    x.add(quote(s));
  return x;
}


static int _hashCode(Object a) {
  return a == null ? 0 : a.hashCode();
}


static boolean arraysEqual(Object[] a, Object[] b) {
  if (a.length != b.length) return false;
  for (int i = 0; i < a.length; i++)
    if (neq(a[i], b[i])) return false;
  return true;
}


static String n2(long l) { return formatWithThousands(l); }
static String n2(AtomicLong l) { return n2(l.get()); }
static String n2(Collection l) { return n2(l(l)); }
static String n2(Map map) { return n2(l(map)); }

static String n2(double l, String singular) {
  return empty(singular) ? str(l) : n2(l, singular, singular + "s");
}

static String n2(double l, String singular, String plural) {
  if (fraction(l) == 0)
    return n2((long) l, singular, plural);
  else
    return l + " " + plural;
}

static String n2(long l, String singular, String plural) {
  return n_fancy2(l, singular, plural);
}

static String n2(long l, String singular) {
  return empty(singular) ? n2(l) : n_fancy2(l, singular, singular + "s");
}

static String n2(Collection l, String singular) {
  return n2(l(l), singular);
}

static String n2(Collection l, String singular, String plural) {
  return n_fancy2(l, singular, plural);
}

static String n2(Map m, String singular, String plural) {
  return n_fancy2(m, singular, plural);
}

static String n2(Map m, String singular) {
  return n2(l(m), singular);
}

static String n2(long[] a, String singular) { return n2(l(a), singular); }

static String n2(Object[] a, String singular) { return n2(l(a), singular); }
static String n2(Object[] a, String singular, String plural) { return n_fancy2(a, singular, plural); }




  static String n2(IMultiMap mm, String singular) { return n2(mm, singular, singular + "s"); }
static String n2(IMultiMap mm, String singular, String plural) {
    return n_fancy2(l(mm), singular, plural);
  }



static <A> List<A> sorted(Collection<A> c, Object comparator) {
  List<A> l = cloneList(c);
  sort(l, makeComparator(comparator));
  return l;
}

static <A> List<A> sorted(Collection<A> c) {
  List<A> l = cloneList(c);
  sort(l);
  return l;
}

static <A> List<A> sorted(Comparator<A> comparator, Collection<A> c) {
  List<A> l = cloneList(c);
  sort(l, comparator);
  return l;
}


static String shortToString(Object o) {
  return shorten(str(o), 100);
}


static <A> Set<A> joinSets(Collection<A>... l) {
  Set<A> set = similarEmptySet(first(l));
  for (Collection<A> o : l)
    if (o != null)
      set.addAll(o);
  return set;
}


static void assertSetEquals(Collection l1, Collection l2) { assertSetEquals("", l1, l2); }
static void assertSetEquals(String msg, Collection l1, Collection l2) {
  assertSetsEqual(msg, l1, l2);
}


static <A, B> Map<A, B> putAll(Map<A, B> a, Map<? extends A,? extends B> b) {
  if (a != null && b != null) a.putAll(b);
  return a;
}


static <A, B> MultiMap<A, B> putAll(MultiMap<A, B> a, Map<? extends A,? extends B> b) {
  if (a != null) a.putAll((Map) b);
  return a;
}


static <A, B> Map<A, B> putAll(Map<A, B> a, Object... b) {
  if (a != null)
    litmap_impl(a, b);
  return a;
}



static <A> void remove(List<A> l, int i) {
  if (l != null && i >= 0 && i < l(l))
    l.remove(i);
}

static <A> void remove(Collection<A> l, A a) {
  if (l != null) l.remove(a);
}

static <A, B> B remove(Map<A, B> map, Object a) {
  return map == null ? null : map.remove(a);
}

static void remove(BitSet bs, int i) {
  bs.clear(i);
}


static <A> A getAndClear(IVar<A> v) {
  A a = v.get();
  v.set(null);
  return a;
}


static <A, B> Set<A> keySet(Map<A, B> map) {
  return map == null ? new HashSet() : map.keySet();
}

static Set keySet(Object map) {
  return keys((Map) map);
}




  static <A, B> Set<A> keySet(MultiMap<A, B> mm) {
    return mm.keySet();
  }





static <A, B> int keysSize(MultiMap<A, B> mm) {
  return lKeys(mm);
}


static <A> A reverseGet(List<A> l, int idx) {
  if (l == null || idx < 0) return null;
  int n = l(l);
  return idx < n ? l.get(n-1-idx) : null;
}


static <A, B> Map<A, B> cloneMap(Map<A, B> map) {
  if (map == null) return new HashMap();
  // assume mutex is equal to map
  synchronized(map) {
    return map instanceof TreeMap ? new TreeMap((TreeMap) map) // copies comparator
      : map instanceof LinkedHashMap ? new LinkedHashMap(map)
      : new HashMap(map);
  }
}

static <A, B> List<B> cloneMap(Iterable<A> l, IF1<A, B> f) {
  List x = emptyList(l);
  if (l != null) for (A o : cloneList(l))
    x.add(f.get(o));
  return x;
}


static <A, B, C extends Collection<B>> List<B> allValues(Map<A, C> map) {
  List<B> out = new ArrayList();
  for (var l : values(map))
    addAll(out, l);
  return out;
}


static Method hashMap_findKey_method;

static <A, B> A hashMap_findKey(HashMap<A, B> map, Object key) { try {
  if (hashMap_findKey_method == null)
    hashMap_findKey_method = findMethodNamed(HashMap.class, "getNode");
  Map.Entry<A, B> entry = (Map.Entry) hashMap_findKey_method.invoke(map, hashMap_internalHash(key), key);
  // java.util.Map.Entry<A, B> entry = (java.util.Map.Entry) call(hash, 'getNode, hashMap_internalHash(key), wkey);
  return entry == null ? null : entry.getKey();
} catch (Exception __e) { throw rethrow(__e); } }


static int hashCodeFor(Object a) {
  return a == null ? 0 : a.hashCode();
}


static String joinNemptiesWithColon(String... strings) {
  return joinNempties(": ", strings);
}

static String joinNemptiesWithColon(Collection<String> strings) {
  return joinNempties(": ", strings);
}


static String commaCombine(Object... l) {
  return joinNemptiesWithComma(flattenCollectionsAndArrays(ll(l)));
}


static int boostHashCombine(int a, int b) {
  return a ^ (b + 0x9e3779b9 + (a << 6) + (a >>> 2));
  
  // OLD (changed) 2022/3/10: ret a ^ (b + 0x9e3779b9 + (a << 6) + (a >> 2));
}


static double sqrt(double x) {
  return Math.sqrt(x);
}


static UnsupportedOperationException unsupportedOperation() {
  throw new UnsupportedOperationException();
}


static Pt longToPt(long l) {
  return new Pt(firstIntFromLong(l), secondIntFromLong(l));
}


static int getWidth(Component c) {
  return c == null ? 0 : (int) swingCall(c, "getWidth");
}


static int getHeight(Component c) {
  return c == null ? 0 : (int) swingCall(c, "getHeight");
}


static Rect rect(int x, int y, int w, int h) {
  return new Rect(x, y, w, h);
}

static Rect rect(Pt p, int w, int h) {
  return new Rect(p.x, p.y, w, h);
}

static Rect rect(int w, int h) {
  return new Rect(0, 0, w, h);
}




static int iceil(double d) {
  return (int) Math.ceil(d);
}


static int hash(Object... l) {
  return hashAboutObjects(l);
}


static int hashCode(Object a) {
  return a == null ? 0 : a.hashCode();
}

static int hashCode(long l) {
  return Long.hashCode(l);
}

static int hashCode(double d) {
  return Double.hashCode(d);
}


static int lLongArray(long[] a) {
  return a == null ? 0 : a.length;
}


static long[] resizeLongArray(long[] a, int n) {
  if (n == lLongArray(a)) return a;
  long[] b = new long[n];
  arraycopy(a, 0, b, 0, Math.min(lLongArray(a), n));
  return b;
}


static int maximumSafeArraySize() {
  return Integer.MAX_VALUE-8;
}


static <A> ArrayList<Long> longArrayToList(long[] a) {
  if (a == null) return null;
  return longArrayToList(a, 0, a.length);
}

// no range checking on from/to in the interest of S P E E E E E EEED
static <A> ArrayList<Long> longArrayToList(long[] a, int from, int to) {
  if (a == null) return null;
  ArrayList < Long > l = new ArrayList<>(to-from);
  for (int i = from; i < to; i++) l.add(a[i]);
  return l;
}


static <A> List<A> asVirtualList(A[] a) {
  return wrapArrayAsList(a);
}


static <A> List<A> listFromFunction(int n, IF1<Integer, A> f) {
  return new RandomAccessAbstractList<A>() {
    public int size() { return n; }
    public A get(int i) { return f.get(i); }
  };
}

static <A> List<A> listFromFunction(IF1<Integer, A> f, int n) {
  return listFromFunction(n, f);
}


static String squareBracket(String s) {
  return "[" + s + "]";
}


static Pt origin() {
  return pt(0, 0);
}


static Color getColor(BufferedImage img, int x, int y) {
  return colorFromRGBA(img.getRGB(x, y));
}

static Color getColor(BufferedImage img, Pt p) {
  return colorFromRGBA(img.getRGB(p.x, p.y));
}


static int rgbInt(int r, int g, int b) {
  return (clamp(r, 0, 255) << 16) | (clamp(g, 0, 255) << 8) | clamp(b, 0, 255);
}


static int asInt(Object o) {
  return toInt(o);
}


static <A> A set(A o, String field, Object value) {
  if (o == null) return null;
  if (o instanceof Class) set((Class) o, field, value);
  else try {
    Field f = set_findField(o.getClass(), field);
    makeAccessible(f);
    smartSet(f, o, value);
  } catch (Exception e) {
    throw new RuntimeException(e);
  }
  return o;
}

static void set(Class c, String field, Object value) {
  if (c == null) return;
  try {
    Field f = set_findStaticField(c, field);
    makeAccessible(f);
    smartSet(f, null, value);
  } catch (Exception e) {
    throw new RuntimeException(e);
  }
}
  
static Field set_findStaticField(Class<?> c, String field) {
  Class _c = c;
  do {
    for (Field f : _c.getDeclaredFields())
      if (f.getName().equals(field) && (f.getModifiers() & java.lang.reflect.Modifier.STATIC) != 0)
        return f;
    _c = _c.getSuperclass();
  } while (_c != null);
  throw new RuntimeException("Static field '" + field + "' not found in " + c.getName());
}

static Field set_findField(Class<?> c, String field) {
  Class _c = c;
  do {
    for (Field f : _c.getDeclaredFields())
      if (f.getName().equals(field))
        return f;
    _c = _c.getSuperclass();
  } while (_c != null);
  throw new RuntimeException("Field '" + field + "' not found in " + c.getName());
}

static void set(BitSet bs, int idx) {
  { if (bs != null) bs.set(idx); }
}


static int parseDigit(char c) {
  return c >= '0' && c <= '9' ? c-'0' : 0;
}

static int parseDigit(String s, int i) {
  return parseDigit(s.charAt(i));
}


static String singleDigitBytesToString(ByteBuffer l) {
  if (l == null) return null;
  int n = l.size();
  char[] data = new char[n];
  for (int i = 0; i < n; i++)
    data[i] = (char) ('0' + ubyteToInt(l.get(i)) % 10);
  return str(data);
}


static int length(Object[] array) {
  return array == null ? 0 : array.length;
}

static int length(List list) {
  return list == null ? 0 : list.size();
}

static int length(String s) {
  return s == null ? 0 : s.length();
}


static Pt translatePt(Pt a, Pt b) {
  return addPts(a, b);
}

static Pt translatePt(int x, int y, Pt a) {
  return addPts(a, pt(x, y));
}

static Pt translatePt(Pt a, int x, int y) {
  return translatePt(x, y, a);
}


static PtBuffer ptBuffer(Iterable<Pt> l) {
  return new PtBuffer(l);
}


static int onePathLookupDirection(Pt p) {
  return indexOf(onePathDirections(), p);
}



  static void assertBetween(long a, long b, long x) {
    { if (x >= a && x <= b) return; }
    throw fail(x + " is not between " + a + " and " + b);
  }


  static void assertBetween(int a, int b, int x) {
    { if (x >= a && x <= b) return; }
    throw fail(x + " is not between " + a + " and " + b);
  }




static int lByteArray(byte[] a) {
  return a == null ? 0 : a.length;
}


static byte[] resizeByteArray(byte[] a, int n) {
  if (n == l(a)) return a;
  byte[] b = new byte[n];
  arraycopy(a, 0, b, 0, min(l(a), n));
  return b;
}


static Object[] toArray(Collection c) {
  return toObjectArray(c);
}

static <A> A[] toArray(Class<A> type, Iterable<A> c) {
  return toArray(c, type);
}

static <A> A[] toArray(Class<A> type, Collection<A> c) {
  return toArray(c, type);
}

static <A> A[] toArray(Collection<A> c, Class<A> type) {
  A[] a = arrayOfType(l(c), type);
  if (a.length == 0) return a;
  asList(c).toArray(a);
  return a;
}

static <A> A[] toArray(Iterable<A> c, Class<A> type) {
  var c2 = asList(c);
  A[] a = arrayOfType(l(c2), type);
  if (a.length == 0) return a;
  c2.toArray(a);
  return a;
}

// array must have correct length and will be filled
static <A> A[] toArray(A[] array, Collection c) {
  if (array == null || c == null) return null;
  asList(c).toArray(array);
  return array;
}


static <A> ArrayList<Byte> byteArrayToList(byte[] a) {
  if (a == null) return null;
  return byteArrayToList(a, 0, a.length);
}

// no range checking on from/to in the interest of speed
static <A> ArrayList<Byte> byteArrayToList(byte[] a, int from, int to) {
  if (a == null) return null;
  ArrayList < Byte > l = new ArrayList<>(to-from);
  for (int i = from; i < to; i++) l.add(a[i]);
  return l;
}


static <A> A popFirst(List<A> l) {
  if (empty(l)) return null;
  A a = first(l);
  l.remove(0);
  return a;
}

static <A> A popFirst(Collection<A> l) {
  if (empty(l)) return null;
  A a = first(l);
  l.remove(a);
  return a;
}

static <A, B> Pair<A, B> popFirst(Map<A, B> map) {
  if (map == null) return null;
  var it = map.entrySet().iterator();
  if (!it.hasNext()) return null;
  var p = mapEntryToPair(it.next());
  it.remove();
  return p;
}

static <A> List<A> popFirst(int n, List<A> l) {
  List<A> part = cloneSubList(l, 0, n);
  removeSubList(l, 0, n);
  return part;
}

static <A> AppendableChain<A> popFirst(AppendableChain<A> a) {
  return a == null ? null : a.popFirst();
}


static <A> A nextToLast(List<A> l) {
  return get(l, l(l)-2);
}


static byte[] subByteArray(byte[] b, int start) {
  return subByteArray(b, start, l(b));
}
  
static byte[] subByteArray(byte[] b, int start, int end) {
  start = max(start, 0); end = min(end, l(b));
  if (start == 0 && end == l(b)) return b;
  if (start >= end) return new byte[0];
  byte[] x = new byte[end-start];
  System.arraycopy(b, start, x, 0, end-start);
  return x;
}






static boolean eqOneOf(Object o, Object... l) {
  for (Object x : l) if (eq(o, x)) return true; return false;
}


static Method findMethod_cached(Object o, String method, Object... args) { try {
  if (o == null) return null;
  if (o instanceof Class) {
    _MethodCache cache = callOpt_getCache((Class) o);
    List<Method> methods = cache.cache.get(method);
    if (methods != null) for (Method m : methods)
      if (isStaticMethod(m) && findMethod_checkArgs(m, args, false))
        return m;
    return null;
  } else {
    _MethodCache cache = callOpt_getCache(o.getClass());
    List<Method> methods = cache.cache.get(method);
    if (methods != null) for (Method m : methods)
      if (findMethod_checkArgs(m, args, false))
        return m;
    return null;
  }
} catch (Exception __e) { throw rethrow(__e); } }



static void addToContainer(Container a, Component... b) {
  if (a == null) return;
  { swing(() -> { 
    for (Component c : unnullForIteration(b))
      if (c != null) 
        a.add(c);
  }); }
}


static long intPairToLong(IntPair p) {
  return p == null ? 0 : (((long) p.a) << 32) | (((long) p.b) & 0xFFFFFFFF);
}

static long intPairToLong(int a, int b) {
  return (((long) a) << 32) | (((long) b) & 0xFFFFFFFF);
}


static boolean endsWith(String a, String b) {
  return a != null && a.endsWith(b);
}

static boolean endsWith(String a, char c) {
  return nempty(a) && lastChar(a) == c;
}


  static boolean endsWith(String a, String b, Matches m) {
    if (!endsWith(a, b)) return false;
    m.m = new String[] {dropLast(l(b), a)};
    return true;
  }




static String quote(Object o) {
  if (o == null) return "null";
  return quote(str(o));
}

static String quote(String s) {
  if (s == null) return "null";
  StringBuilder out = new StringBuilder((int) (l(s)*1.5+2));
  quote_impl(s, out);
  return out.toString();
}
  
static void quote_impl(String s, StringBuilder out) {
  out.append('"');
  int l = s.length();
  for (int i = 0; i < l; i++) {
    char c = s.charAt(i);
    if (c == '\\' || c == '"')
      out.append('\\').append(c);
    else if (c == '\r')
      out.append("\\r");
    else if (c == '\n')
      out.append("\\n");
    else if (c == '\t')
      out.append("\\t");
    else if (c == '\0')
      out.append("\\0");
    else
      out.append(c);
  }
  out.append('"');
}


static String formatWithThousands(long l) {
  return formatWithThousandsSeparator(l);
}


static double fraction(double d) {
  return d % 1;
}


static String n_fancy2(long l, String singular, String plural) {
  return formatWithThousandsSeparator(l) + " " + trim(l == 1 ? singular : plural);
}

static String n_fancy2(Collection l, String singular, String plural) {
  return n_fancy2(l(l), singular, plural);
}

static String n_fancy2(Map m, String singular, String plural) {
  return n_fancy2(l(m), singular, plural);
}

static String n_fancy2(Object[] a, String singular, String plural) {
  return n_fancy2(l(a), singular, plural);
}




static <T> void sort(T[] a, Comparator<? super T> c) {
  if (a != null) Arrays.sort(a, c);
}

static <T> void sort(T[] a) {
  if (a != null) Arrays.sort(a);
}

static void sort(int[] a) { if (a != null) Arrays.sort(a); }

static <T> void sort(List<T> a, Comparator<? super T> c) {
  if (a != null) Collections.sort(a, c);
}

static void sort(List a) {
  if (a != null) Collections.sort(a);
}


static Comparator makeComparator(final Object f) {
  if (f instanceof Comparator) return (Comparator) f;
  return new Comparator() {
    public int compare(Object a, Object b) {
      return (Integer) callF(f, a, b);
    }
  };
}



static int shorten_default = 100;

static String shorten(CharSequence s) { return shorten(s, shorten_default); }

static String shorten(CharSequence s, int max) {
  return shorten(s, max, "...");
}

static String shorten(CharSequence s, int max, String shortener) {
  if (s == null) return "";
  if (max < 0) return str(s);
  return s.length() <= max ? str(s) : subCharSequence(s, 0, min(s.length(), max-l(shortener))) + shortener;
}

static String shorten(int max, CharSequence s) { return shorten(s, max); }


static Set similarEmptySet(Iterable m) {
  if (m instanceof TreeSet) return new TreeSet(((TreeSet) m).comparator());
  if (m instanceof LinkedHashSet) return new LinkedHashSet();
  
  return new HashSet();
}

static Set similarEmptySet(Map m) {
  if (m instanceof TreeMap) return new TreeSet(((TreeMap) m).comparator());
  if (m instanceof LinkedHashMap) return new LinkedHashSet();
  
  return new HashSet();
}


static void assertSetsEqual(Collection l1, Collection l2) { assertSetsEqual("", l1, l2); }
static void assertSetsEqual(String msg, Collection l1, Collection l2) {
  assertEquals("Set sizes", l(l1), l(l2));
  
  Set set2 = asSet(l2);
  for (Object o : unnullForIteration(l1))
    if (!contains(set2, o))
      throw fail("Set 2 doesn't contain " + o);
  Set set1 = asSet(l1);
  for (Object o : unnullForIteration(l2))
    if (!contains(set1, o))
      throw fail("Set 1 doesn't contain " + o);
}


static HashMap litmap(Object... x) {
  HashMap map = new HashMap();
  litmap_impl(map, x);
  return map;
}

static void litmap_impl(Map map, Object... x) {
  if (x != null) for (int i = 0; i < x.length-1; i += 2)
    if (x[i+1] != null)
      map.put(x[i], x[i+1]);
}


static <A, B> int lKeys(MultiMap<A, B> mm) {
  return mm == null ? 0 : mm.keysSize();
}


// This is a bit rough... finds static and non-static methods.

static Method findMethodNamed(Object obj, String method) {
  if (obj == null) return null;
  if (obj instanceof Class)
    return findMethodNamed((Class) obj, method);
  return findMethodNamed(obj.getClass(), method);
}

static Method findMethodNamed(Class c, String method) {
  while (c != null) {
    for (Method m : c.getDeclaredMethods())
      if (m.getName().equals(method)) {
        makeAccessible(m);
        return m;
      }
    c = c.getSuperclass();
  }
  return null;
}


static int hashMap_internalHash(Object key) {
  int h;
  return (key == null) ? 0 : (h = key.hashCode()) ^ (h >>> 16);
}


static String joinNempties(String sep, Object... strings) {
  return joinStrings(sep, strings);
}

static String joinNempties(String sep, Iterable strings) {
  return joinStrings(sep, strings);
}


static String joinNemptiesWithComma(Object... strings) {
  return joinNempties(", ", strings);
}

static String joinNemptiesWithComma(Iterable strings) {
  return joinNempties(", ", strings);
}


static List flattenCollectionsAndArrays(Iterable a) {
  List l = new ArrayList();
  for (Object x : a)
    if (x instanceof Collection)
      l.addAll(flattenCollectionsAndArrays((Collection) x));
    else if (x instanceof Object[])
      l.addAll(flattenCollectionsAndArrays(asList((Object[]) x)));
    else
      l.add(x);
  return l;
}


static int firstIntFromLong(long l) {
  return (int) (l >> 32);
}


static int secondIntFromLong(long l) {
  return (int) l;
}


static Object swingCall(final Object o, final String method, final Object... args) {
  return swing(new F0<Object>() { public Object get() { try {  return call(o, method, args);  } catch (Exception __e) { throw rethrow(__e); } }
  public String toString() { return "return call(o, method, args);"; }});
}


static int hashAboutObjects(Object... l) {
  int hash = 0, n = l(l);
  for (int i = 0; i < n; i++)
    hash = boostHashCombine(hash, hashCode(l[i]));
  return hash;
}


static Color colorFromRGBA(int rgba) {
  return new Color(rgba, true);
}


static float clamp(float x, float a, float b) {
  return x < a ? a : x > b ? b : x;
}

static double clamp(double x, double a, double b) {
  return x < a ? a : x > b ? b : x;
}

static int clamp(int x, int a, int b) {
  return x < a ? a : x > b ? b : x;
}

static long clamp(long x, long a, long b) {
  return x < a ? a : x > b ? b : x;
}


static void smartSet(Field f, Object o, Object value) throws Exception {
  try {
    f.set(o, value);
  } catch (Exception e) {
    Class type = f.getType();
    
    // take care of common case (long to int)
    if (type == int.class && value instanceof Long)
      { f.set(o, ((Long) value).intValue()); return; }
      
    if (type == boolean.class && value instanceof String)
      { f.set(o, isTrueOrYes(((String) value))); return; }
    
    if (type == LinkedHashMap.class && value instanceof Map)
      { f.set(o, asLinkedHashMap((Map) value)); return; }
    
    
    throw e;
  }
}


static int ubyteToInt(byte b) {
  return b & 0x0FF;
}

static int ubyteToInt(char c) {
  return c & 0x0FF;
}


// binary legacy signature
static Object[] toObjectArray(Collection c) {
  return toObjectArray((Iterable) c);
}

static Object[] toObjectArray(Iterable c) {
  List l = asList(c);
  return l.toArray(new Object[l.size()]);
}



static <A> A[] arrayOfType(Class<A> type, int n) {
  return makeArray(type, n);
}

static <A> A[] arrayOfType(int n, Class<A> type) {
  return arrayOfType(type, n);
}




static char lastChar(String s) {
  return empty(s) ? '\0' : s.charAt(l(s)-1);
}


static <A> A[] dropLast(A[] a) { return dropLast(a, 1); }
static <A> A[] dropLast(A[] a, int n) {
  if (a == null) return null;
  n = Math.min(n, a.length);
  A[] b = arrayOfSameType(a, a.length-n);
  System.arraycopy(a, 0, b, 0, b.length);
  return b;
}

static <A> List<A> dropLast(List<A> l) {
  return subList(l, 0, l(l)-1);
}

static <A> List<A> dropLast(int n, List<A> l) {
  return subList(l, 0, l(l)-n);
}

static <A> List<A> dropLast(Iterable<A> l) {
  return dropLast(asList(l));
}

static String dropLast(String s) {
  return substring(s, 0, l(s)-1);
}

static String dropLast(String s, int n) {
  return substring(s, 0, l(s)-n);
}

static String dropLast(int n, String s) {
  return dropLast(s, n);
}





static String formatWithThousandsSeparator(long l) {
  return NumberFormat.getInstance(new Locale("en_US")).format(l);
}


static String trim(String s) { return s == null ? null : s.trim(); }
static String trim(StringBuilder buf) { return buf.toString().trim(); }
static String trim(StringBuffer buf) { return buf.toString().trim(); }


static CharSequence subCharSequence(CharSequence s, int x) {
  return subCharSequence(s, x, s == null ? 0 : s.length());
}

static CharSequence subCharSequence(CharSequence s, int x, int y) {
  if (s == null) return null;
  if (x < 0) x = 0;
  if (x >= s.length()) return "";
  if (y < x) y = x;
  if (y > s.length()) y = s.length();
  return s.subSequence(x, y);
}


static Set asSet(Object[] array) {
  HashSet set = new HashSet();
  for (Object o : array)
    if (o != null)
      set.add(o);
  return set;
}

static Set<String> asSet(String[] array) {
  TreeSet<String> set = new TreeSet();
  for (String o : array)
    if (o != null)
      set.add(o);
  return set;
}

static <A> Set<A> asSet(Iterable<A> l) {
  if (l instanceof Set) return (Set) l;
  HashSet<A> set = new HashSet();
  for (A o : unnull(l))
    if (o != null)
      set.add(o);
  return set;
}




static String joinStrings(String sep, Object... strings) {
  return joinStrings(sep, Arrays.asList(strings));
}

static String joinStrings(String sep, Iterable strings) {
  StringBuilder buf = new StringBuilder();
  for (Object o : unnull(strings)) { 
    String s = strOrNull(o);
    if (nempty(s)) {
      if (nempty(buf)) buf.append(sep);
      buf.append(s);
    }
  }
  return str(buf);
}


static boolean isTrueOrYes(Object o) {
  return isTrueOpt(o) || o instanceof String && (eqicOneOf(((String) o), "1", "t", "true") || isYes(((String) o)));
}


static <A, B> LinkedHashMap<A, B> asLinkedHashMap(Map<A, B> map) {
  if (map instanceof LinkedHashMap) return (LinkedHashMap) map;
  LinkedHashMap<A, B> m = new LinkedHashMap();
  if (map != null) synchronized(collectionMutex(map)) {
    m.putAll(map);
  }
  return m;
}


static <A> A[] makeArray(Class<A> type, int n) {
  return (A[]) Array.newInstance(type, n);
}




static <A> A[] arrayOfSameType(A[] a, int n) {
  return newObjectArrayOfSameType(a, n);
}


static boolean isTrueOpt(Object o) {
  if (o instanceof Boolean)
    return ((Boolean) o).booleanValue();
  return false;
}

static boolean isTrueOpt(String field, Object o) {
  return isTrueOpt(getOpt(field, o));
}


static boolean eqicOneOf(String s, String... l) {
  for (String x : l) if (eqic(s, x)) return true; return false;
}


static List<String> isYes_yesses = litlist("y", "yes", "yeah", "y", "yup", "yo", "corect", "sure", "ok", "afirmative"); // << collapsed words, so "corect" means "correct"

static boolean isYes(String s) {
  return isYes_yesses.contains(collapseWord(toLowerCase(firstWord2(s))));
}




static <A> A[] newObjectArrayOfSameType(A[] a) { return newObjectArrayOfSameType(a, a.length); }
static <A> A[] newObjectArrayOfSameType(A[] a, int n) {
  return (A[]) Array.newInstance(a.getClass().getComponentType(), n);
}


static <A> ArrayList<A> litlist(A... a) {
  ArrayList l = new ArrayList(a.length);
  for (A x : a) l.add(x);
  return l;
}


static String collapseWord(String s) {
  if (s == null) return "";
  StringBuilder buf = new StringBuilder();
  for (int i = 0; i < l(s); i++)
    if (i == 0 || !charactersEqualIC(s.charAt(i), s.charAt(i-1)))
      buf.append(s.charAt(i));
  return buf.toString();
}


static List<String> toLowerCase(List<String> strings) {
  List<String> x = new ArrayList();
  for (String s : strings)
    x.add(s.toLowerCase());
  return x;
}

static String[] toLowerCase(String[] strings) {
  String[] x = new String[l(strings)];
  for (int i = 0; i < l(strings); i++)
    x[i] = strings[i].toLowerCase();
  return x;
}

static String toLowerCase(String s) {
  return s == null ? "" : s.toLowerCase();
}


static String firstWord2(String s) {
  s = xltrim(s);
  if (empty(s)) return "";
  if (isLetterOrDigit(first(s)))
    return takeCharsWhile(__32 -> isLetterOrDigit(__32), s);
  else return "" + first(s);
}




static boolean charactersEqualIC(char c1, char c2) {
  if (c1 == c2) return true;
  char u1 = Character.toUpperCase(c1);
  char u2 = Character.toUpperCase(c2);
  if (u1 == u2) return true;
  return Character.toLowerCase(u1) == Character.toLowerCase(u2);
}



static String xltrim(String s) {
  int i = 0, n = l(s);
  while (i < n && contains(" \t\r\n", s.charAt(i)))
    ++i;
  return substr(s, i);
}


static boolean isLetterOrDigit(char c) {
  return Character.isLetterOrDigit(c);
}


// pred: char -> bool
static String takeCharsWhile(String s, Object pred) {
  int i = 0;
  while (i < l(s) && isTrue(callF(pred, s.charAt(i)))) ++i;
  return substring(s, 0, i);
}

static String takeCharsWhile(IF1<Character, Boolean> f, String s) {
  return takeCharsWhile(s, f);
}




static String substr(String s, int x) {
  return substring(s, x);
}

static String substr(String s, int x, int y) {
  return substring(s, x, y);
}




// AppendableChain has one "smart" head element (with size counter
// and pointer to the chain's last element), all the other nodes are
// maximally simple (MinimalChain).
// This allows O(1) front insertion, front removal and back insertion
// (not removal at the back though) which is fine for what I need this
// for (event queues).
//
// Stefan Reich, Oct 21

static class AppendableChain<A> extends MinimalChain<A> implements Iterable<A> {
  MinimalChain<A> last; // pointer to last element in chain (which may be us)
  int size; // total length of chain

  AppendableChain() {} // only used internally
  AppendableChain(A element) {
  this.element = element; size = 1; last = this; }
  
  // intermediate constructor called by itemPlusChain()
  AppendableChain(A element, AppendableChain<A> next) {
  this.next = next;
  this.element = element;
    if (next == null) return;
    
    MinimalChain<A> b = new MinimalChain();
    b.element = next.element;
    b.next = next.next;
    this.next = b;
    last = next.last;
    size = next.size+1;
  }
  
  public String toString() { return str(toList()); }
  
  // append at the end
  boolean add(A a) {
    MinimalChain newLast = new MinimalChain(a);
    last.next = newLast;
    last = newLast;
    ++size;
    return true;
  }
  
  // drop first element
  AppendableChain<A> popFirst() {
    if (next == null) return null;
    element = next.element;
    if (last == next) last = this;
    next = next.next;
    --size;
    return this;
  }
  
  ArrayList<A> toList() {
    ArrayList<A> l = emptyList(size);
    MinimalChain<A> c = this;
    while (c != null) {
      l.add(c.element);
      c = c.next;
    }
    return l;
  }
  
  //public Iterator<A> iterator() { ret toList().iterator(); }
  
  class ACIt extends IterableIterator  < A > {
    MinimalChain<A> c = AppendableChain.this;
    
    public boolean hasNext() {
      return c != null;
    }
    
    public A next() {
      var a = c.element;
      c = c.next;
      return a;
    }
  }
  
  public IterableIterator<A> iterator() {
    return new ACIt();
  }
}
static final class IntPair implements Comparable<IntPair> , IFieldsToList{
  int a;
  int b;
  IntPair() {}
  IntPair(int a, int b) {
  this.b = b;
  this.a = a;}
  public String toString() { return shortClassName_dropNumberPrefix(this) + "(" + a + ", " + b + ")"; }public Object[] _fieldsToList() { return new Object[] {a, b}; }

  public boolean equals(Object o) {
    if (!(o instanceof IntPair)) return false;
    IntPair x =  (IntPair) o;
    return a == x.a && b == x.b;
  }

  public int hashCode() {
    int h = -672893111;
    h = boostHashCombine(h, _hashCode(a));
    h = boostHashCombine(h, _hashCode(b));
    return h;
  }
  
  public int compareTo(IntPair p) {
    if (p == null) return 1;
    int pa = p.a;
    if (a < pa) return -1;
    if (a > pa) return 1;
    return Integer.compare(b, p.b);
  }
}


static class MinimalChain<A> implements Iterable<A> {
  A element;
  MinimalChain<A> next;

  MinimalChain() {}
  MinimalChain(A element) {
  this.element = element;}
  MinimalChain(A element, MinimalChain<A> next) {
  this.next = next;
  this.element = element;}
  
  public String toString() { return str(toList()); }
  
  ArrayList<A> toList() {
    ArrayList<A> l = new ArrayList();
    MinimalChain<A> c = this;
    while (c != null) {
      l.add(c.element);
      c = c.next;
    }
    return l;
  }
  
  void setElement(A a) { element = a; }
  void setNext(MinimalChain<A> next) { this.next = next; }
  
  // TODO: optimize
  public Iterator<A> iterator() { return toList().iterator(); }
  
  A get() { return element; }
}

}