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 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 javax.imageio.*;
import java.math.*;


class main {
public static void main(final String[] args) throws Exception {
  for (String s : ll(null, "", "\r", "\n", "\r\n", "abc", "a\rb", "a\r", "a\r\r\nb", "a\r\rb", "a\n", "\n\r\n", "a\n\nbla", "a\r\nb\r\n"))
    assertEqualsVerbose(fixNewLines(s), fixNewLines_old(s));
}
static <A> List<A> ll(A... a) {
  ArrayList l = new ArrayList(a.length);
  for (A x : a) l.add(x);
  return l;
}
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 Map<Thread, Boolean> _registerThread_threads = newWeakHashMap();

static Thread _registerThread(Thread t) {
  _registerThread_threads.put(t, true);
  return t;
}

static void _registerThread() { _registerThread(Thread.currentThread()); }
static void assertEqualsVerbose(Object x, Object y) {
  assertEqualsVerbose((String) null, x, y);
}

static void assertEqualsVerbose(String msg, Object x, Object y) {
  if (!eq(x, y)) {
    if (x instanceof String && y instanceof String && (containsNewLine((String) x) || containsNewLine((String) y)))
      nlPrintNL(unidiff((String) x, (String) y));

    throw fail((msg != null ? msg + ": " : "") + sfu(y) + " != " + sfu(x));
  } else
    print("OK: " + sfu(x));
}


static String fixNewLines_old(String s) {
  return s.replace("\r\n", "\n").replace("\r", "\n");
}


static boolean containsNewLine(String s) {
  return contains(s, '\n'); // screw \r, nobody needs it
}
static String sfu(Object o) { return structureForUser(o); }
static <A, B> Map<A, B> newWeakHashMap() {
  return _registerWeakMap(synchroMap(new WeakHashMap()));
}
static boolean eq(Object a, Object b) {
  return a == null ? b == null : a == b || a.equals(b);
}


static void nlPrintNL(Object o) {
  print_doubleNL(o);
}
static String unidiff(String a, String b) {
  int contextSize = 1;
  return fromLines(BlockDiffer.generateUniDiff(toLines(a), toLines(b), contextSize));
}
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(String msg) { throw new RuntimeException(msg == null ? "" : msg); }
static RuntimeException fail(String msg, Throwable innerException) { throw new RuntimeException(msg, innerException); }

static volatile StringBuffer local_log = new StringBuffer(); // not redirected
static volatile StringBuffer 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 int print_maxLineLength = 0; // 0 = unset

static boolean print_silent; // 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 void print() {
  print("");
}

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

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

static void print_noNewLine(String s) {
  
  Object f = print_byThread == null ? null : print_byThread.get();
  if (f == null) f = print_allThreads;
  if (f != null)
    if (isFalse(f instanceof F1 ? ((F1) f).get(s) : callF(f, s))) return;
  

  print_raw(s);
}

static void print_raw(String s) {
  s = fixNewLines(s);
  // TODO if (print_maxLineLength != 0)
  StringBuffer loc = local_log;
  StringBuffer 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);
  System.out.print(s);
}

static void print_append(StringBuffer buf, String s, int max) {
  synchronized(buf) {
    buf.append(s);
    max /= 2;
    if (buf.length() > max) 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);
    }
  }
}
static <A> int indexOf(List<A> l, A a, int startIndex) {
  if (l == null) return -1;
  for (int i = startIndex; i < l(l); 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) {
  if (x == null) return -1;
  for (int i = 0; i < l(x); i++)
    if (eq(x[i], a))
      return i;
  return -1;
}


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

static <A, B> Map<A, B> synchroMap(Map<A, B> map) {
  return Collections.synchronizedMap(map);
}
static volatile boolean ping_pauseAll;
static int ping_sleep = 100; // poll pauseAll flag every 100

static volatile boolean ping_anyActions;
static Map<Thread, Object> ping_actions = newWeakHashMap();


// always returns true
static boolean ping() {
  if (ping_pauseAll  || ping_anyActions ) ping_impl();
  return true;
}

// returns true when it slept
static boolean ping_impl() { try {
  if (ping_pauseAll && !isAWTThread()) {
    do
      Thread.sleep(ping_sleep);
    while (ping_pauseAll);
    return true;
  }
  
  
  if (ping_anyActions) {
    Object action;
    synchronized(ping_actions) {
      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 WeakHashMap<Class, ArrayList<Method>> callF_cache = new WeakHashMap();


  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 Object callF(Object f, Object... args) { try {
  if (f instanceof String)
    return callMC((String) f, 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) {
    
    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));
} catch (Exception __e) { throw rethrow(__e); } }

// 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")) {
        m.setAccessible(true);
        l.add(m);
      }
    if (!l.isEmpty()) break;
    _c = _c.getSuperclass();
  } while (_c != null);
  callF_cache.put(c, l);
  return l;
}
// usually L<S>
static String fromLines(Collection lines) {
  StringBuilder buf = new StringBuilder();
  if (lines != null)
    for (Object line : lines)
      buf.append(str(line)).append('\n');
  return buf.toString();
}

static String fromLines(String... lines) {
  return fromLines(asList(lines));
}
static RuntimeException asRuntimeException(Throwable t) {
  
  if (t instanceof Error)
    _handleError((Error) t);
  
  return t instanceof RuntimeException ? (RuntimeException) t : new RuntimeException(t);
}
static void print_doubleNL(Object o) {
  print("\n" + str(o) + "\n");
}
static IterableIterator<String> toLines(File f) {
  return linesFromFile(f);
}

static List<String> toLines(String s) {
  List<String> lines = new ArrayList<String>();
  if (s == null) return lines;
  int start = 0;
  while (true) {
    int i = toLines_nextLineBreak(s, start);
    if (i < 0) {
      if (s.length() > start) lines.add(s.substring(start));
      break;
    }

    lines.add(s.substring(start, i));
    if (s.charAt(i) == '\r' && i+1 < s.length() && s.charAt(i+1) == '\n')
      i += 2;
    else
      ++i;

    start = i;
  }
  return lines;
}

static int toLines_nextLineBreak(String s, int start) {
  for (int i = start; i < s.length(); i++) {
    char c = s.charAt(i);
    if (c == '\r' || c == '\n')
      return i;
  }
  return -1;
}
static String structureForUser(Object o) {
  return beautifyStructure(struct_noStringSharing(o));
}
static boolean isFalse(Object o) {
  return eq(false, o);
}
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(int[] a) { return a == null ? 0 : a.length; }
static int l(float[] 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(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(Object o) {
  return o == null ? 0
    : o instanceof String ? l((String) o)
    : o instanceof Map ? l((Map) o)
    : o instanceof Collection ? l((Collection) o)
    : (Integer) call(o, "size");
}




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

static String str(char[] c) {
  return new String(c);
}
static boolean contains(Collection c, Object o) {
  return c != null && c.contains(o);
}

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 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 String beautifyStructure(String s) {
  return structure_addTokenMarkers(s);
}
// TODO: send hard errors to core

static AtomicLong _handleError_nonVMErrors = new AtomicLong();
static AtomicLong _handleError_vmErrors = new AtomicLong();
static AtomicLong _handleError_outOfMemoryErrors = new AtomicLong();
static volatile long _handleError_lastOutOfMemoryError;
static volatile Error _handleError_lastHardError;

static void _handleError(Error e) {
  if (!(e instanceof VirtualMachineError)) {
    incAtomicLong(_handleError_nonVMErrors);
    return;
  }
  
  print("\nHARD ERROR\n");
  printStackTrace2(e);
  print("\nHARD ERROR\n");
  _handleError_lastHardError = e;
  
  incAtomicLong(_handleError_vmErrors);
  if (e instanceof OutOfMemoryError) {
    incAtomicLong(_handleError_outOfMemoryErrors);
    _handleError_lastOutOfMemoryError = sysNow();
  }
}
static String struct_noStringSharing(Object o) {
  structure_Data d = new structure_Data();
  d.noStringSharing = true;
  return structure(o, d);
}
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 matching arguments 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) {
          m.setAccessible(true);
          multiMapPut(callMC_cache, m.getName(), m);
        }
      c = c.getSuperclass();
    }
  }
}
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) {
  ArrayList<Integer> l = new ArrayList();
  for (int i : a) l.add(i);
  return l;
}

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 Class javax() {
  return getJavaX();
}
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> List<A> synchroList() {
  return Collections.synchronizedList(new ArrayList<A>());
}

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

// 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 RuntimeException rethrow(Throwable t) {
  
  if (t instanceof Error)
    _handleError((Error) t);
  
  throw t instanceof RuntimeException ? (RuntimeException) t : new RuntimeException(t);
}
static Thread currentThread() {
  return Thread.currentThread();
}
static IterableIterator<String> linesFromFile(File f) { try {
  if (!f.exists()) return emptyIterableIterator();
  if (ewic(f.getName(), ".gz"))
    return linesFromReader(utf8bufferedReader(newGZIPInputStream(f)));
  return linesFromReader(utf8bufferedReader(f));
} catch (Exception __e) { throw rethrow(__e); } }
static void printException(Throwable e) {
  printStackTrace(e);
}
static Object call(Object o) {
  return callFunction(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) { try {
  if (o == null) return null;
  if (o instanceof Class) {
    Method m = call_findStaticMethod((Class) o, method, args, false);
    m.setAccessible(true);
    return invokeMethod(m, null, args);
  } else {
    Method m = call_findMethod(o, method, args, false);
    m.setAccessible(true);
    return invokeMethod(m, o, args);
  }
} catch (Exception __e) { throw rethrow(__e); } }

static Method call_findStaticMethod(Class c, String method, Object[] args, boolean debug) {
  Class _c = c;
  while (c != null) {
    for (Method m : c.getDeclaredMethods()) {
      if (debug)
        System.out.println("Checking method " + m.getName() + " with " + m.getParameterTypes().length + " parameters");;
      if (!m.getName().equals(method)) {
        if (debug) System.out.println("Method name mismatch: " + method);
        continue;
      }

      if ((m.getModifiers() & java.lang.reflect.Modifier.STATIC) == 0 || !call_checkArgs(m, args, debug))
        continue;

      return m;
    }
    c = c.getSuperclass();
  }
  throw new RuntimeException("Method '" + method + "' (static) with " + args.length + " parameter(s) not found in " + _c.getName());
}

static Method call_findMethod(Object o, String method, Object[] args, boolean debug) {
  Class c = o.getClass();
  while (c != null) {
    for (Method m : c.getDeclaredMethods()) {
      if (debug)
        System.out.println("Checking method " + m.getName() + " with " + m.getParameterTypes().length + " parameters");;
      if (m.getName().equals(method) && call_checkArgs(m, args, debug))
        return m;
    }
    c = c.getSuperclass();
  }
  throw new RuntimeException("Method '" + method + "' (non-static) with " + args.length + " parameter(s) not found in " + o.getClass().getName());
}

private static boolean call_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 Map synchroHashMap() {
  return Collections.synchronizedMap(new HashMap());
}

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 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 Throwable getExceptionCause(Throwable e) {
  Throwable c = e.getCause();
  return c != null ? c : e;
}
static String joinWithSpace(Collection<String> c) {
  return join(" ", c);
}

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

static Object callFunction(Object f, Object... args) {
  return callF(f, args);
}
static List<String> classNames(Collection l) {
  return getClassNames(l);
}

static List<String> classNames(Object[] l) {
  return getClassNames(Arrays.asList(l));
}
static Class mc() {
  return main.class;
}
static String structure_addTokenMarkers(String s) {
  List<String> tok = javaTok(s);
  
  // find references
  
  TreeSet<Integer> refs = new TreeSet();
  for (int i = 1; i < l(tok); i += 2) {
    String t = tok.get(i);
    if (t.startsWith("t") && isInteger(t.substring(1)))
      refs.add(parseInt(t.substring(1)));
  }
  
  if (empty(refs)) return s;
  
  // add markers
  for (int i : refs) {
    int idx = i*2+1;
    String t = "";
    if (endsWithLetterOrDigit(tok.get(idx-1))) t = " ";
    tok.set(idx, t + "m" + i + " " + tok.get(idx));
  }
  
  return join(tok);
}
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);
}
// extended over Class.isInstance() to handle primitive types
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 Throwable printStackTrace(Throwable e) {
  // we go to system.out now - system.err is nonsense
  print(getStackTrace(e));
  return e;
}

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

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

/*static void printStackTrace(S indent, Throwable e) {
  if (endsWithLetter(indent)) indent += " ";
  printIndent(indent, getStackTrace(e));
}*/
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 long sysNow() {
  return System.nanoTime()/1000000;
}
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 void incAtomicLong(AtomicLong l) {
  l.incrementAndGet();
}
static Class __javax;

static Class getJavaX() { try {
  
  return __javax;
} catch (Exception __e) { throw rethrow(__e); } }
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 BufferedReader utf8bufferedReader(InputStream in) { try {
  return new BufferedReader(new InputStreamReader(in, "UTF-8"));
} catch (Exception __e) { throw rethrow(__e); } }

static BufferedReader utf8bufferedReader(File f) { try {
  return utf8bufferedReader(newFileInputStream(f));
} catch (Exception __e) { throw rethrow(__e); } }
static IterableIterator<String> linesFromReader(Reader r) {
  final BufferedReader br = bufferedReader(r);
  return iteratorFromFunction_f0(new F0<String>() { String get() { try { return  readLineFromReaderWithClose(br) ; } catch (Exception __e) { throw rethrow(__e); } }
  public String toString() { return "readLineFromReaderWithClose(br)"; }});
}
static boolean structure_showTiming, structure_checkTokenCount;

static String structure(Object o) {
  return structure(o, new structure_Data());
}

static String structure(Object o, structure_Data d) {
  StringWriter sw = new StringWriter();
  d.out = new PrintWriter(sw);
  structure_go(o, d);
  String s = str(sw);
  if (structure_checkTokenCount) {
    print("token count=" + d.n);
    assertEquals("token count", l(javaTokC(s)), d.n);
  }
  return s;
}

static void structure_go(Object o, structure_Data d) {
  structure_1(o, d);
  while (nempty(d.stack))
    popLast(d.stack).run();
}

static void structureToPrintWriter(Object o, PrintWriter out) {
  structure_Data d = new structure_Data();
  d.out = out;
  structure_go(o, d);
}

// leave to false, unless unstructure() breaks
static boolean structure_allowShortening = false;

static class structure_Data {
  PrintWriter out;
  int stringSizeLimit;
  int shareStringsLongerThan = 20;
  boolean noStringSharing;

  IdentityHashMap<Object,Integer> seen = new IdentityHashMap();
  //new BitSet refd;
  HashMap<String,Integer> strings = new HashMap();
  HashSet<String> concepts = new HashSet();
  HashMap<Class, List<Field>> fieldsByClass = new HashMap();
  int n; // token count
  List<Runnable> stack = new ArrayList();
  
  // append single token
  structure_Data append(String token) { out.print(token); ++n; return this; }
  structure_Data append(int i) { out.print(i); ++n; return this; }
  
  // append multiple tokens
  structure_Data append(String token, int tokCount) { out.print(token); n += tokCount; return this; }
  
  // extend last token
  structure_Data app(String token) { out.print(token); return this; }
  structure_Data app(int i) { out.print(i); return this; }
}

static void structure_1(final Object o, final structure_Data d) {
  if (o == null) { d.append("null"); return; }
  
  Class c = o.getClass();
  boolean concept = false;
  
  List<Field> lFields = d.fieldsByClass.get(c);
  
  if (lFields == null) {
    // these are never back-referenced (for readability)
    
    if (o instanceof Number) {
      PrintWriter out = d.out;
if (o instanceof Integer) { int i = ((Integer) o).intValue(); out.print(i); d.n += i < 0 ? 2 : 1; return; }
      if (o instanceof Long) { long l = ((Long) o).longValue(); out.print(l); out.print("L"); d.n += l < 0 ? 2 : 1; return; }
      if (o instanceof Short) { short s = ((Short) o).shortValue(); d.append("sh ", 2); out.print(s); d.n += s < 0 ? 2 : 1; return; }
      if (o instanceof Float) { d.append("fl ", 2); quoteToPrintWriter(str(o), out); return; }
      if (o instanceof Double) { d.append("d(", 3); quoteToPrintWriter(str(o), out); d.append(")"); return; }
      if (o instanceof BigInteger) { out.print("bigint("); out.print(o); out.print(")"); d.n += ((BigInteger) o).signum() < 0 ? 5 : 4; return; }
    }
  
    if (o instanceof Boolean) {
      d.append(((Boolean) o).booleanValue() ? "t" : "f"); return;
    }
      
    if (o instanceof Character) {
      d.append(quoteCharacter((Character) o)); return;
    }
      
    if (o instanceof File) {
      d.append("File ").append(quote(((File) o).getPath())); return;
    }
      
    // referencable objects follow
    
    Integer ref = d.seen.get(o);
    if (o instanceof String && ref == null) ref = d.strings.get((String) o);
    if (ref != null) { /*d.refd.set(ref);*/ d.append("t").app(ref); return; }

    if (!(o instanceof String))
      d.seen.put(o, d.n); // record token number
    else {
      String s = d.stringSizeLimit != 0 ? shorten((String) o, d.stringSizeLimit) : (String) o;
      if (!d.noStringSharing) {
        if (d.shareStringsLongerThan == Integer.MAX_VALUE)
          d.seen.put(o, d.n);
        if (l(s) >= d.shareStringsLongerThan)
          d.strings.put(s, d.n);
      }
      quoteToPrintWriter(s, d.out); d.n++; return;
    }
      
    if (o instanceof HashSet) {
      d.append("hashset ");
      structure_1(new ArrayList((Set) o), d);
      return;
    }
  
    if (o instanceof TreeSet) {
      d.append("treeset ");
      structure_1(new ArrayList((Set) o), d);
      return;
    }
    
    String name = c.getName();
    if (o instanceof Collection
      && !startsWith(name, "main$")
      /* && neq(name, "main$Concept$RefL") */) {
      d.append("[");
      final int l = d.n;
      final Iterator it = ((Collection) o).iterator();
      d.stack.add(new Runnable() { public void run() { try { 
        if (!it.hasNext())
          d.append("]");
        else {
          d.stack.add(this);
          if (d.n != l) d.append(", ");
          structure_1(it.next(), d);
        }
      
} catch (Exception __e) { throw rethrow(__e); } }  public String toString() { return "if (!it.hasNext())\r\n          d.append(\"]\");\r\n        else {\r\n          d.sta..."; }});
      return;
    }
    
    if (o instanceof Map && !startsWith(name, "main$")) {
      if (o instanceof LinkedHashMap) d.append("lhm");
      else if (o instanceof HashMap) d.append("hm");
      else if (name.equals("java.util.Collections$SynchronizedMap")) d.append("sync");
      else if (name.equals("java.util.Collections$SynchronizedSortedMap")) { d.append("sync tm", 2); }
      
      d.append("{");
      final int l = d.n;
      final Iterator it = ((Map) o).entrySet().iterator();
      
      d.stack.add(new Runnable() {
        boolean v;
        Map.Entry e;
        
        public void run() {
          if (v) {
            d.append("=");
            v = false;
            d.stack.add(this);
            structure_1(e.getValue(), d);
          } else {
            if (!it.hasNext())
              d.append("}");
            else {
              e = (Map.Entry) it.next();
              v = true;
              d.stack.add(this);
              if (d.n != l) d.append(", ");
              structure_1(e.getKey(), d);
            }
          }
        }
      });
      return;
    }
    
    if (c.isArray()) {
      if (o instanceof byte[]) {
        d.append("ba ").append(quote(bytesToHex((byte[]) o))); return;
      }
  
      final int n = Array.getLength(o);
  
      if (o instanceof boolean[]) {
        String hex = boolArrayToHex((boolean[]) o);
        int i = l(hex);
        while (i > 0 && hex.charAt(i-1) == '0' && hex.charAt(i-2) == '0') i -= 2;
        d.append("boolarray ").append(n).app(" ").append(quote(substring(hex, 0, i))); return;
      }
      
      String atype = "array", sep = ", ";
  
      if (o instanceof int[]) {
        //ret "intarray " + quote(intArrayToHex((int[]) o));
        atype = "intarray";
        sep = " ";
      }
      
      d.append(atype).append("{");
      d.stack.add(new Runnable() {
        int i;
        public void run() {
          if (i >= n)
            d.append("}");
          else {
            d.stack.add(this);
            if (i > 0) d.append(", ");
            structure_1(Array.get(o, i++), d);
          }
        }
      });
      return;
    }
  
    if (o instanceof Class) {
      d.append("class(", 2).append(quote(((Class) o).getName())).append(")"); return;
    }
      
    if (o instanceof Throwable) {
      d.append("exception(", 2).append(quote(((Throwable) o).getMessage())).append(")"); return;
    }
      
    if (o instanceof BitSet) {
      BitSet bs = (BitSet) o;
      d.append("bitset{", 2);
      int l = d.n;
      for (int i = bs.nextSetBit(0); i >= 0; i = bs.nextSetBit(i+1)) {
        if (d.n != l) d.append(", ");
        d.append(i);
      }
      d.append("}"); return;
    }
      
    // Need more cases? This should cover all library classes...
    if (name.startsWith("java.") || name.startsWith("javax.")) {
      d.append("j ").append(quote(str(o))); return; // Hm. this is not unstructure-able
    }
    
    
      
    /*if (name.equals("main$Lisp")) {
      fail("lisp not supported right now");
    }*/
    
    String dynName = shortDynamicClassName(o);
    if (concept && !d.concepts.contains(dynName)) {
      d.concepts.add(dynName);
      d.append("c ");
    }
    
    // serialize an object with fields.
    // first, collect all fields and values in fv.
    
    TreeSet<Field> fields = new TreeSet<Field>(new Comparator<Field>() {
      public int compare(Field a, Field b) {
        return stdcompare(a.getName(), b.getName());
      }
    });
    
    Class cc = c;
    while (cc != Object.class) {
      for (Field field : getDeclaredFields_cached(cc)) {
        if ((field.getModifiers() & (java.lang.reflect.Modifier.STATIC | java.lang.reflect.Modifier.TRANSIENT)) != 0)
          continue;
        String fieldName = field.getName();
        
        fields.add(field);
        
        // put special cases here...
      }
        
      cc = cc.getSuperclass();
    }
    
    lFields = asList(fields);
    
    // Render this$1 first because unstructure needs it for constructor call.
    
    for (int i = 0; i < l(lFields); i++) {
      Field f = lFields.get(i);
      if (f.getName().equals("this$1")) {
        lFields.remove(i);
        lFields.add(0, f);
        break;
      }
    }
  
    
    d.fieldsByClass.put(c, lFields);
  } // << if (lFields == null)
  else { // ref handling for lFields != null
    Integer ref = d.seen.get(o);
    if (ref != null) { /*d.refd.set(ref);*/ d.append("t").app(ref); return; }
    d.seen.put(o, d.n); // record token number
  }

  LinkedHashMap<String,Object> fv = new LinkedHashMap();
  for (Field f : lFields) {
    Object value;
    try {
      value = f.get(o);
    } catch (Exception e) {
      value = "?";
    }
      
    if (value != null)
      fv.put(f.getName(), value);
    
  }
  
  String name = c.getName();
  String shortName = dropPrefix("main$", name);
    
  // Now we have fields & values. Process fieldValues if it's a DynamicObject.
  
  // omit field "className" if equal to class's name
  if (concept && eq(fv.get("className"), shortName))
    fv.remove("className");
          
  if (o instanceof DynamicObject) {
    fv.putAll((Map) fv.get("fieldValues"));
    fv.remove("fieldValues");
    shortName = shortDynamicClassName(o);
    fv.remove("className");
  }
  
  String singleField = fv.size() == 1 ? first(fv.keySet()) : null;
  
  d.append(shortName);
  
  
  final int l = d.n;
  final Iterator it = fv.entrySet().iterator();
  
  d.stack.add(new Runnable() { public void run() { try { 
    if (!it.hasNext()) {
      if (d.n != l)
        d.append(")");
    } else {
      Map.Entry e = (Map.Entry) it.next();
      d.append(d.n == l ? "(" : ", ");
      d.append((String) e.getKey()).append("=");
      d.stack.add(this);
      structure_1(e.getValue(), d);
    }
  
} catch (Exception __e) { throw rethrow(__e); } }  public String toString() { return "if (!it.hasNext()) {\r\n      if (d.n != l)\r\n        d.append(\")\");\r\n    } else..."; }});
}

static GZIPInputStream newGZIPInputStream(File f) {
  return gzInputStream(f);
}

static GZIPInputStream newGZIPInputStream(InputStream in) {
  return gzInputStream(in);
}
static Throwable printStackTrace2(Throwable e) {
  // we go to system.out now - system.err is nonsense
  print(getStackTrace2(e));
  return e;
}

static void printStackTrace2() {
  printStackTrace2(new Throwable());
}

static void printStackTrace2(String msg) {
  printStackTrace2(new Throwable(msg));
}

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 FileInputStream newFileInputStream(File path) throws IOException {
  return newFileInputStream(path.getPath());
}

static FileInputStream newFileInputStream(String path) throws IOException {
  FileInputStream f = new // Line break for ancient translator
    FileInputStream(path);
  //callJavaX("registerIO", f, path, true);
  return f;
}
static BufferedReader bufferedReader(Reader r) {
  return r instanceof BufferedReader ? (BufferedReader) r : new BufferedReader(r);
}
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 == '\0')
      out.append("\\0");
    else
      out.append(c);
  }
  out.append('"');
}
static int shorten_default = 100;

static String shorten(String s) { return shorten(s, shorten_default); }

static String shorten(String s, int max) {
  return shorten(s, max, "...");
}

static String shorten(String s, int max, String shortener) {
  if (s == null) return "";
  if (max < 0) return s;
  return s.length() <= max ? s : substring(s, 0, min(s.length(), max-l(shortener))) + shortener;
}

static String shorten(int max, String s) { return shorten(s, max); }
static String quoteCharacter(char c) {
  if (c == '\'') return "'\\''";
  if (c == '\\') return "'\\\\'";
  if (c == '\r') return "'\\r'";
  if (c == '\n') return "'\\n'";
  if (c == '\t') return "'\\t'";
  return "'" + c + "'";
}

public static String join(String glue, Iterable<String> strings) {
  if (strings == null) return "";
  StringBuilder buf = new StringBuilder();
  Iterator<String> 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));
}

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

static String join(Iterable<String> 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 String getStackTrace2(Throwable e) {
  return hideCredentials(getStackTrace(unwrapTrivialExceptionWraps(e)) + replacePrefix("java.lang.RuntimeException: ", "FAIL: ",
    hideCredentials(str(getInnerException(e)))) + "\n");
}
static String shortDynamicClassName(Object o) {
 if (o instanceof DynamicObject && ((DynamicObject) o).className != null)
    return ((DynamicObject) o).className;
  return shortClassName(o);
}
static String dropPrefix(String prefix, String s) {
  return s == null ? null : s.startsWith(prefix) ? s.substring(l(prefix)) : s;
}
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;
  m.m = new String[] { substring(a, 0, l(a)-l(b)) };
  return true;
}
// TODO: extended multi-line strings

static int javaTok_n, javaTok_elements;
static boolean javaTok_opt;

static List<String> javaTok(String s) {
  ++javaTok_n;
  ArrayList<String> tok = new ArrayList();
  int l = s.length();
  
  int i = 0, n = 0;
  while (i < l) {
    int j = i;
    char c, d;
    
    // scan for whitespace
    while (j < l) {
      c = s.charAt(j);
      d = j+1 >= l ? '\0' : s.charAt(j+1);
      if (c == ' ' || c == '\t' || c == '\r' || c == '\n')
        ++j;
      else if (c == '/' && d == '*') {
        do ++j; while (j < l && !s.substring(j, Math.min(j+2, l)).equals("*/"));
        j = Math.min(j+2, l);
      } else if (c == '/' && d == '/') {
        do ++j; while (j < l && "\r\n".indexOf(s.charAt(j)) < 0);
      } else
        break;
    }
    
    tok.add(javaTok_substringN(s, i, j));
    ++n;
    i = j;
    if (i >= l) break;
    c = s.charAt(i);
    d = i+1 >= l ? '\0' : s.charAt(i+1);

    // scan for non-whitespace
    
    // Special JavaX syntax: 'identifier
    if (c == '\'' && Character.isJavaIdentifierStart(d) && i+2 < l && "'\\".indexOf(s.charAt(i+2)) < 0) {
      j += 2;
      while (j < l && Character.isJavaIdentifierPart(s.charAt(j)))
        ++j;
    } else if (c == '\'' || c == '"') {
      char opener = c;
      ++j;
      while (j < l) {
        int c2 = s.charAt(j);
        if (c2 == opener || c2 == '\n' && opener == '\'') { // allow multi-line strings, but not for '
          ++j;
          break;
        } else if (c2 == '\\' && j+1 < l)
          j += 2;
        else
          ++j;
      }
    } else if (Character.isJavaIdentifierStart(c))
      do ++j; while (j < l && (Character.isJavaIdentifierPart(s.charAt(j)) || "'".indexOf(s.charAt(j)) >= 0)); // for stuff like "don't"
    else if (Character.isDigit(c)) {
      do ++j; while (j < l && Character.isDigit(s.charAt(j)));
      if (j < l && s.charAt(j) == 'L') ++j; // Long constants like 1L
    } else if (c == '[' && d == '[') {
      do ++j; while (j+1 < l && !s.substring(j, j+2).equals("]]"));
      j = Math.min(j+2, l);
    } else if (c == '[' && d == '=' && i+2 < l && s.charAt(i+2) == '[') {
      do ++j; while (j+2 < l && !s.substring(j, j+3).equals("]=]"));
      j = Math.min(j+3, l);
    } else
      ++j;
      
    tok.add(javaTok_substringC(s, i, j));
    ++n;
    i = j;
  }
  
  if ((tok.size() % 2) == 0) tok.add("");
  javaTok_elements += tok.size();
  return tok;
}

static List<String> javaTok(List<String> tok) {
  return javaTokWithExisting(join(tok), tok);
}
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 List<String> javaTokC(String s) {
  if (s == null) return null;
  int l = s.length();
  ArrayList<String> tok = new ArrayList();
  
  int i = 0;
  while (i < l) {
    int j = i;
    char c, d;
    
    // scan for whitespace
    while (j < l) {
      c = s.charAt(j);
      d = j+1 >= l ? '\0' : s.charAt(j+1);
      if (c == ' ' || c == '\t' || c == '\r' || c == '\n')
        ++j;
      else if (c == '/' && d == '*') {
        do ++j; while (j < l && !s.substring(j, Math.min(j+2, l)).equals("*/"));
        j = Math.min(j+2, l);
      } else if (c == '/' && d == '/') {
        do ++j; while (j < l && "\r\n".indexOf(s.charAt(j)) < 0);
      } else
        break;
    }
    
    i = j;
    if (i >= l) break;
    c = s.charAt(i);
    d = i+1 >= l ? '\0' : s.charAt(i+1);

    // scan for non-whitespace
    if (c == '\'' || c == '"') {
      char opener = c;
      ++j;
      while (j < l) {
        if (s.charAt(j) == opener || s.charAt(j) == '\n') { // end at \n to not propagate unclosed string literal errors
          ++j;
          break;
        } else if (s.charAt(j) == '\\' && j+1 < l)
          j += 2;
        else
          ++j;
      }
    } else if (Character.isJavaIdentifierStart(c))
      do ++j; while (j < l && (Character.isJavaIdentifierPart(s.charAt(j)) || "'".indexOf(s.charAt(j)) >= 0)); // for stuff like "don't"
    else if (Character.isDigit(c)) {
      do ++j; while (j < l && Character.isDigit(s.charAt(j)));
      if (j < l && s.charAt(j) == 'L') ++j; // Long constants like 1L
    } else if (c == '[' && d == '[') {
      do ++j; while (j+1 < l && !s.substring(j, j+2).equals("]]"));
      j = Math.min(j+2, l);
    } else if (c == '[' && d == '=' && i+2 < l && s.charAt(i+2) == '[') {
      do ++j; while (j+2 < l && !s.substring(j, j+3).equals("]=]"));
      j = Math.min(j+3, l);
    } else
      ++j;
      
    tok.add(javaTok_substringC(s, i, j));
    i = j;
  }
  
  return tok;
}
static <A> A assertEquals(Object x, A y) {
  return assertEquals(null, x, y);
}

static <A> A assertEquals(String msg, Object x, A y) {
  if (!(x == null ? y == null : x.equals(y)))
    throw fail((msg != null ? msg + ": " : "") + y + " != " + x);
  return y;
}
static Map<Class, Field[]> getDeclaredFields_cache = newDangerousWeakHashMap();

static Field[] getDeclaredFields_cached(Class c) {
  Field[] fields;
  synchronized(getDeclaredFields_cache) {
    fields = getDeclaredFields_cache.get(c);
    if (fields == null) {
      getDeclaredFields_cache.put(c, fields = c.getDeclaredFields());
      for (Field f : fields)
        f.setAccessible(true);
    }
  }
  return fields;
}
static String readLineFromReaderWithClose(BufferedReader r) { try {
  String s = r.readLine();
  if (s == null) r.close();
  return s;
} catch (Exception __e) { throw rethrow(__e); } }
static String boolArrayToHex(boolean[] a) {
  return bytesToHex(boolArrayToBytes(a));
}
static boolean endsWithLetterOrDigit(String s) {
  return nempty(s) && isLetterOrDigit(lastCharacter(s));
}
static int gzInputStream_defaultBufferSize = 65536;

static GZIPInputStream gzInputStream(File f) { try {
  return gzInputStream(new FileInputStream(f));
} catch (Exception __e) { throw rethrow(__e); } }

static GZIPInputStream gzInputStream(File f, int bufferSize) { try {
  return new GZIPInputStream(new FileInputStream(f), bufferSize);
} catch (Exception __e) { throw rethrow(__e); } }

static GZIPInputStream gzInputStream(InputStream in) { try {
  return new GZIPInputStream(in, gzInputStream_defaultBufferSize);
} catch (Exception __e) { throw rethrow(__e); } }
static Object first(Object list) {
  return empty((List) list) ? null : ((List) list).get(0);
}

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



static Iterator emptyIterator() {
  return Collections.emptyIterator();
}
static boolean empty(Collection c) { return c == null || c.isEmpty(); }
static boolean empty(String 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(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(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; }


  public static String bytesToHex(byte[] bytes) {
    return bytesToHex(bytes, 0, bytes.length);
  }

  public static String bytesToHex(byte[] bytes, int ofs, int len) {
    StringBuilder stringBuilder = new StringBuilder(len*2);
    for (int i = 0; i < len; i++) {
      String s = "0" + Integer.toHexString(bytes[ofs+i]);
      stringBuilder.append(s.substring(s.length()-2, s.length()));
    }
    return stringBuilder.toString();
  }

static boolean isInteger(String s) {
  if (s == null) return false;
  int n = l(s);
  if (n == 0) return false;
  int i = 0;
  if (s.charAt(0) == '-')
    if (++i >= n) return false;
  while (i < n) {
    char c = s.charAt(i);
    if (c < '0' || c > '9') return false;
    ++i;
  }
  return true;
}
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 void quoteToPrintWriter(String s, PrintWriter out) {
  if (s == null) { out.print("null"); return; }
  out.print('"');
  int l = s.length();
  for (int i = 0; i < l; i++) {
    char c = s.charAt(i);
    if (c == '\\' || c == '"') {
      out.print('\\'); out.print(c);
    } else if (c == '\r')
      out.print("\\r");
    else if (c == '\n')
      out.print("\\n");
    else if (c == '\0')
      out.print("\\0");
    else
      out.print(c);
  }
  out.print('"');
}
static <A> IterableIterator<A> iteratorFromFunction_f0(final F0<A> f) {
  class IFF2 extends IterableIterator<A> {
    A a;
    boolean done;
    
    public boolean hasNext() {
      getNext();
      return !done;
    }
    
    public A next() {
      getNext();
      if (done) throw fail();
      A _a = a;
      a = null;
      return _a;
    }
    
    void getNext() {
      if (done || a != null) return;
      a = f.get();
      done = a == null;
    }
  };
  return new IFF2();
}
static String substring(String s, int x) {
  return substring(s, x, l(s));
}

static String substring(String 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.substring(x, y);
}


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

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

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

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

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

static boolean nempty(Object o) { return !empty(o); }
static int parseInt(String s) {
  return empty(s) ? 0 : Integer.parseInt(s);
}

static int parseInt(char c) {
  return Integer.parseInt(str(c));
}
static <A> A popLast(List<A> l) {
  return liftLast(l);
}
static int stdcompare(Number a, Number b) {
  return cmp(a, b);
}

static int stdcompare(String a, String b) {
  return cmp(a, b);
}

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

static int stdcompare(Object a, Object b) {
  return cmp(a, b);
}

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

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


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


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




// 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 javaTok_substringC(String s, int i, int j) {
  return s.substring(i, j);
}
static String javaTok_substringN(String s, int i, int j) {
  if (i == j) return "";
  if (j == i+1 && s.charAt(i) == ' ') return " ";
  return s.substring(i, j);
}
static byte[] boolArrayToBytes(boolean[] a) {
  byte[] b = new byte[(l(a)+7)/8];
  for (int i = 0; i < l(a); i++)
    if (a[i])
      b[i/8] |= 1 << (i & 7);
  return b;
}
static String replacePrefix(String prefix, String replacement, String s) {
  if (!startsWith(s, prefix)) return s;
  return replacement + substring(s, l(prefix));
}
static String getType(Object o) {
  return getClassName(o);
}
static <A> A liftLast(List<A> l) {
  if (l.isEmpty()) return null;
  int i = l(l)-1;
  A a = l.get(i);
  l.remove(i);
  return a;
}
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(String a, String b) {
  return a == null ? b == null ? 0 : -1 : a.compareTo(b);
}

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

static String hideCredentials(String url) {
  return url.replaceAll("([&?])(_pass|key)=[^&\\s\"]*", "$1$2=<hidden>");
}

static String hideCredentials(Object o) {
  return hideCredentials(str(o));
}
static boolean regionMatchesIC(String a, int offsetA, String b, int offsetB, int len) {
  
  
    return a != null && a.regionMatches(true, offsetA, b, offsetB, len);
  
}
static Throwable getInnerException(Throwable e) {
  while (e.getCause() != null)
    e = e.getCause();
  return e;
}
static char lastCharacter(String s) {
  return empty(s) ? 0 : s.charAt(l(s)-1);
}
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 Throwable unwrapTrivialExceptionWraps(Throwable e) {
  if (e == null) return e;
  while (e.getClass() == RuntimeException.class
    && e.getCause() != null && eq(e.getMessage(), str(e.getCause())))
    e = e.getCause();
  return e;
}
static boolean neq(Object a, Object b) {
  return !eq(a, b);
}
static boolean isLetterOrDigit(char c) {
  return Character.isLetterOrDigit(c);
}
static List<String> javaTokWithExisting(String s, List<String> existing) {
  ++javaTok_n;
  int nExisting = javaTok_opt && existing != null ? existing.size() : 0;
  ArrayList<String> tok = existing != null ? new ArrayList(nExisting) : new ArrayList();
  int l = s.length();
  
  int i = 0, n = 0;
  while (i < l) {
    int j = i;
    char c, d;
    
    // scan for whitespace
    while (j < l) {
      c = s.charAt(j);
      d = j+1 >= l ? '\0' : s.charAt(j+1);
      if (c == ' ' || c == '\t' || c == '\r' || c == '\n')
        ++j;
      else if (c == '/' && d == '*') {
        do ++j; while (j < l && !s.substring(j, Math.min(j+2, l)).equals("*/"));
        j = Math.min(j+2, l);
      } else if (c == '/' && d == '/') {
        do ++j; while (j < l && "\r\n".indexOf(s.charAt(j)) < 0);
      } else
        break;
    }
    
    if (n < nExisting && javaTokWithExisting_isCopyable(existing.get(n), s, i, j))
      tok.add(existing.get(n));
    else
      tok.add(javaTok_substringN(s, i, j));
    ++n;
    i = j;
    if (i >= l) break;
    c = s.charAt(i);
    d = i+1 >= l ? '\0' : s.charAt(i+1);

    // scan for non-whitespace
    
    // Special JavaX syntax: 'identifier
    if (c == '\'' && Character.isJavaIdentifierStart(d) && i+2 < l && "'\\".indexOf(s.charAt(i+2)) < 0) {
      j += 2;
      while (j < l && Character.isJavaIdentifierPart(s.charAt(j)))
        ++j;
    } else if (c == '\'' || c == '"') {
      char opener = c;
      ++j;
      while (j < l) {
        if (s.charAt(j) == opener /*|| s.charAt(j) == '\n'*/) { // allow multi-line strings
          ++j;
          break;
        } else if (s.charAt(j) == '\\' && j+1 < l)
          j += 2;
        else
          ++j;
      }
    } else if (Character.isJavaIdentifierStart(c))
      do ++j; while (j < l && (Character.isJavaIdentifierPart(s.charAt(j)) || "'".indexOf(s.charAt(j)) >= 0)); // for stuff like "don't"
    else if (Character.isDigit(c)) {
      do ++j; while (j < l && Character.isDigit(s.charAt(j)));
      if (j < l && s.charAt(j) == 'L') ++j; // Long constants like 1L
    } else if (c == '[' && d == '[') {
      do ++j; while (j+1 < l && !s.substring(j, j+2).equals("]]"));
      j = Math.min(j+2, l);
    } else if (c == '[' && d == '=' && i+2 < l && s.charAt(i+2) == '[') {
      do ++j; while (j+2 < l && !s.substring(j, j+3).equals("]=]"));
      j = Math.min(j+3, l);
    } else
      ++j;
      
    if (n < nExisting && javaTokWithExisting_isCopyable(existing.get(n), s, i, j))
      tok.add(existing.get(n));
    else
      tok.add(javaTok_substringC(s, i, j));
    ++n;
    i = j;
  }
  
  if ((tok.size() % 2) == 0) tok.add("");
  javaTok_elements += tok.size();
  return tok;
}

static boolean javaTokWithExisting_isCopyable(String t, String s, int i, int j) {
  return t.length() == j-i
    && s.regionMatches(i, t, 0, j-i); // << could be left out, but that's brave
}
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 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 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 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>() { 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;
  }
  
  try {
    call(javax(), "_registerDangerousWeakMap", map, init);
  } catch (Throwable e) { _handleException(e);
    upgradeJavaXAndRestart();
  }
  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 PersistableThrowable persistableThrowable(Throwable e) {
  return e == null ? null : new PersistableThrowable(e);
}


static void upgradeJavaXAndRestart() {
  
    run("#1001639");
    restart();
    sleep();
  
  
}
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 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);
}
static volatile Throwable _handleException_lastException;
static List _handleException_onException = synchroList(ll("printStackTrace2"));

static void _handleException(Throwable e) {
  _handleException_lastException = e;
  for (Object f : cloneList(_handleException_onException)) try {
    callF(f, e);
  } catch (Throwable e2) {
    printStackTrace2(e2); // pcall could lead to endless loops
  }
}


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

static void sleep(long ms) {
  ping();
  if (ms < 0) return;
  // allow spin locks
  if (isAWTThread() && ms > 100) throw fail("Should not sleep on AWT thread");
  try {
    Thread.sleep(ms);
  } catch (Exception e) { throw new RuntimeException(e); }
}

static void sleep() { try {
  if (sleep_noSleep) throw fail("nosleep");
  print("Sleeping.");
  sleepQuietly();
} catch (Exception __e) { throw rethrow(__e); } }
static void restart() {
  Object j = getJavaX();
  call(j, "cleanRestart", get(j, "fullArgs"));
}
static Class run(String progID, String... args) {
  Class main = hotwire(progID);
  callMain(main, args);
  return main;
}


// 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 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) {
      f.setAccessible(true);
      return f.get(o);
    }
      
    
      if (o instanceof DynamicObject)
        return ((DynamicObject) o).fieldValues.get(field);
    
  } catch (Exception e) {
    throw asRuntimeException(e);
  }
  throw new RuntimeException("Field '" + field + "' not found in " + o.getClass().getName());
}

static Object get_raw(Object o, String field) {
  try {
    Field f = get_findField(o.getClass(), field);
    f.setAccessible(true);
    return f.get(o);
  } catch (Exception e) {
    throw new RuntimeException(e);
  }
}

static Object get(Class c, String field) {
  try {
    Field f = get_findStaticField(c, field);
    f.setAccessible(true);
    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 <A> A callMain(A c, String... args) {
  callOpt(c, "main", new Object[] {args});
  return c;
}

static void callMain() {
  callMain(mc());
}
static Object collectionMutex(Object o) {
  String c = className(o);
  if (eq(c, "java.util.TreeMap$KeySet"))
    c = className(o = getOpt(o, "m"));
  else if (eq(c, "java.util.HashMap$KeySet"))
    c = className(o = get_raw(o, "this$0"));

  
  
  if (eqOneOf(c, "java.util.TreeMap$AscendingSubMap", "java.util.TreeMap$DescendingSubMap"))
    c = className(o = get_raw(o, "m"));
    
  
    
  return o;
}
static Object sleepQuietly_monitor = new Object();

static void sleepQuietly() { try {
  assertFalse(isAWTThread());
  synchronized(sleepQuietly_monitor) { sleepQuietly_monitor.wait(); }
} catch (Exception __e) { throw rethrow(__e); } }
static Class<?> hotwire(String src) {
  assertFalse(_inCore());
  Class j = getJavaX();
  if (isAndroid()) {
    synchronized(j) { // hopefully this goes well...
      List<File> libraries = new ArrayList<File>();
      File srcDir = (File) call(j, "transpileMain", src, libraries);
      if (srcDir == null)
        throw fail("transpileMain returned null (src=" + quote(src) + ")");
    
      Object androidContext = get(j, "androidContext");
      return (Class) call(j, "loadx2android", srcDir, src);
    }
  } else {
    
    
    Class c = (Class) ( call(j, "hotwire", src));
    hotwire_copyOver(c);
    return c;
    
  }
}


static boolean _inCore() {
  return false;
}
static String className(Object o) {
  return getClassName(o);
}
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 void hotwire_copyOver(Class c) {
  synchronized(StringBuffer.class) {
    for (String field : litlist("print_log", "print_silent", "androidContext")) {
      Object o = getOpt(mc(), field);
      if (o != null)
        setOpt(c, field, o);
    }
      
    Object mainBot = getMainBot();
    if (mainBot != null)
      setOpt(c, "mainBot", mainBot);

    setOpt(c, "creator_class", new WeakReference(mc()));
  }
}
static boolean eqOneOf(Object o, Object... l) {
  for (Object x : l) if (eq(o, x)) return true; return false;
}
static Object callOpt(Object o) {
  if (o == null) return null;
  return callF(o);
}

static Object callOpt(Object o, String method, Object... args) {
  try {
    if (o == null) return null;
    if (o instanceof Class) {
      Method m = callOpt_findStaticMethod((Class) o, method, args, false);
      if (m == null) return null;
      m.setAccessible(true);
      return invokeMethod(m, null, args);
    } else {
      Method m = callOpt_findMethod(o, method, args, false);
      if (m == null) return null;
      m.setAccessible(true);
      return invokeMethod(m, o, args);
    }
  } catch (Exception e) {
    //fail(e.getMessage() + " | Method: " + method + ", receiver: " + className(o) + ", args: (" + join(", ", map(f className, args) + ")");
    throw rethrow(e);
  }
}

static Method callOpt_findStaticMethod(Class c, String method, Object[] args, boolean debug) {
  Class _c = c;
  while (c != null) {
    for (Method m : c.getDeclaredMethods()) {
      if (debug)
        System.out.println("Checking method " + m.getName() + " with " + m.getParameterTypes().length + " parameters");;
      if (!m.getName().equals(method)) {
        if (debug) System.out.println("Method name mismatch: " + method);
        continue;
      }

      if ((m.getModifiers() & java.lang.reflect.Modifier.STATIC) == 0 || !callOpt_checkArgs(m, args, debug))
        continue;

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

static Method callOpt_findMethod(Object o, String method, Object[] args, boolean debug) {
  Class c = o.getClass();
  while (c != null) {
    for (Method m : c.getDeclaredMethods()) {
      if (debug)
        System.out.println("Checking method " + m.getName() + " with " + m.getParameterTypes().length + " parameters");;
      if (m.getName().equals(method) && callOpt_checkArgs(m, args, debug))
        return m;
    }
    c = c.getSuperclass();
  }
  return null;
}

private static boolean callOpt_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 void assertFalse(Object o) {
  if (!(eq(o, false) /*|| isFalse(pcallF(o))*/))
    throw fail(str(o));
}
  
static boolean assertFalse(boolean b) {
  if (b) throw fail("oops");
  return b;
}

static boolean assertFalse(String msg, boolean b) {
  if (b) throw fail(msg);
  return b;
}

static Object getOpt(Object o, String field) {
  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;
    f.setAccessible(true);
    return f.get(o);
  } catch (Exception e) {
    throw new RuntimeException(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;
    f.setAccessible(true);
    return f.get(null);
  } catch (Exception e) {
    throw new RuntimeException(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 Object mainBot;

static Object getMainBot() {
  return mainBot;
}
static <A> ArrayList<A> litlist(A... a) {
  ArrayList l = new ArrayList(a.length);
  for (A x : a) l.add(x);
  return l;
}
//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 Object getOpt_cached(Object o, String field) { try {
  if (o == null) return null;

  Class c = o.getClass();
  HashMap<String, Field> map;
  synchronized(getOpt_cache) {
    map = getOpt_cache.get(c);
    if (map == null)
      map = getOpt_makeCache(c);
  }
  
  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 ((DynamicObject) o).fieldValues.get(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();
    Class _c = c;
    do {
      for (Field f : _c.getDeclaredFields()) {
        f.setAccessible(true);
        String name = f.getName();
        if (!map.containsKey(name))
          map.put(name, f);
      }
      _c = _c.getSuperclass();
    } while (_c != null);
  }
  getOpt_cache.put(c, map);
  return map;
}
static Field setOpt_findField(Class c, String field) {
  HashMap<String, Field> map;
  synchronized(getOpt_cache) {
    map = getOpt_cache.get(c);
    if (map == null)
      map = getOpt_makeCache(c);
  }
  return map.get(field);
}

static void setOpt(Object o, String field, Object value) { try {
  if (o == null) return;
  
  
  
  Class c = o.getClass();
  HashMap<String, Field> map;
  
  synchronized(getOpt_cache) {
    map = getOpt_cache.get(c);
    if (map == null)
      map = getOpt_makeCache(c);
  }
  
  if (map == getOpt_special) {
    if (o instanceof Class) {
      setOpt((Class) o, field, value);
      return;
    }
    
    // It's probably a subclass of Map. Use raw method
    setOpt_raw(o, field, value);
    return;
  }
  
  Field f = map.get(field);
  if (f != null)
    smartSet(f, o, value); // possible improvement: skip setAccessible
} catch (Exception __e) { throw rethrow(__e); } }

static void setOpt(Class c, String field, Object value) {
  if (c == null) return;
  try {
    Field f = setOpt_findStaticField(c, field);
    if (f != null)
      smartSet(f, null, value);
  } catch (Exception e) {
    throw new RuntimeException(e);
  }
}
  
static Field setOpt_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) {
        f.setAccessible(true);
        return f;
      }
    _c = _c.getSuperclass();
  } while (_c != null);
  return null;
}


static <A, B> void put(Map<A, B> map, A a, B b) {
  if (map != null) map.put(a, b);
}
static void setOpt_raw(Object o, String field, Object value) { try {
  if (o == null) return;
  if (o instanceof Class) setOpt_raw((Class) o, field, value);
  else {
    Field f = setOpt_raw_findField(o.getClass(), field);
    if (f != null) {
      f.setAccessible(true);
      smartSet(f, o, value);
    }
  }
} catch (Exception __e) { throw rethrow(__e); } }

static void setOpt_raw(Class c, String field, Object value) { try {
  if (c == null) return;
  Field f = setOpt_raw_findStaticField(c, field);
  if (f != null) {
    f.setAccessible(true);
    smartSet(f, null, value);
  }
} catch (Exception __e) { throw rethrow(__e); } }
  
static Field setOpt_raw_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 Field setOpt_raw_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 boolean isSubtypeOf(Class a, Class b) {
  return b.isAssignableFrom(a); // << always hated that method, let's replace it!
}
static void clear(Collection c) {
  if (c != null) c.clear();
}
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)
      value = ((Long) value).intValue();
    
    if (type == LinkedHashMap.class && value instanceof Map)
      { f.set(o, asLinkedHashMap((Map) value)); return; }
    
    
    throw e;
  }
}


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 abstract class VF1<A> {
  abstract void get(A a);
}
static class BlockDiff {
  public CopyBlock asCopyBlock() { return null; }
  public NewBlock  asNewBlock () { return null; }
}

static class CopyBlock extends BlockDiff {
  int firstLine, lines;

  CopyBlock(int firstLine, int lines) {
    this.firstLine = firstLine;
    this.lines = lines;
  }

  public CopyBlock asCopyBlock() { return this; }
  public int getFirstLine() { return firstLine; }
  public int getLines() { return lines; }
}

static class NewBlock extends BlockDiff {
  int originalStart;
  List<String> contents;

  NewBlock(int originalStart, List<String> contents) {
    this.originalStart = originalStart;
    this.contents = contents;
  }

  public NewBlock  asNewBlock () { return this; }

  public int getOriginalStart() {
    return originalStart;
  }

  public List<String> getContents() {
    return contents;
  }
}

static class ExplodedLine {
  int type;
  String left, right;
  int leftIndex, rightIndex;

  ExplodedLine(int type, String left, String right, int leftIndex, int rightIndex) {
    this.type = type;
    this.left = left;
    this.right = right;
    this.leftIndex = leftIndex;
    this.rightIndex = rightIndex;
  }
  
  public int getType() {
    return type;
  }

  public String getLeft() {
    return left;
  }

  public String getRight() {
    return right;
  }

  public int getLeftIndex() {
    return leftIndex;
  }

  public int getRightIndex() {
    return rightIndex;
  }
}

static class BlockDiffer {
  public static final int IDENTICAL = 0;
  public static final int DIFFERENT = 1;
  public static final int LEFT_ONLY = 2;
  public static final int RIGHT_ONLY = 3;

  private static void printChange(EGDiff.change change) {
    if (change != null) {
      System.out.println("line0="+change.line0+", line1="+change.line1
        +", inserted="+change.inserted+", deleted="+change.deleted);
      printChange(change.link);
    }
  }


  /** Generates the text content of a Unified-format context diff between 2 files
   *  (NB the 'files-changed' header must be added separately).
   */
  public static List<String> generateUniDiff(List<String> fileA, List<String> fileB, int contextSize) {
    EGDiff diff = new EGDiff(fileA.toArray(), fileB.toArray());
    EGDiff.change change = diff.diff_2(false);

    if (change != null) {
      int inserted, deleted;
      List<String> hunkLines = new ArrayList<String>();
      int cumulExtraLinesBwrtA = 0;

      // Each hunk is generated with a header
      do {
        int line0 = change.line0, line1 = change.line1;
        int changeStart = ((line1 < line0) ? line1 : line0);
        int contextStart = ((changeStart > contextSize) ? changeStart - contextSize : 0);
        int headerPosn = hunkLines.size();

        // Provide the first lines of context
        for (int i = contextStart; i < changeStart; i++)
          //System.out.println(" " + fileA.get(i));
          hunkLines.add(" " + fileA.get(i));

        boolean hunkFinish = false;
        // Step through each change giving the change lines and following context
        do {
          inserted = change.inserted;
          deleted = change.deleted;
          line0 = change.line0;
          line1 = change.line1;

          if (line1 < line0) // An insert comes earlier
            while (inserted-- > 0)
              hunkLines.add("+" + fileB.get(line1++));
          while (deleted-- > 0)
            hunkLines.add("-" + fileA.get(line0++));
          while (inserted-- > 0)
            hunkLines.add("+" + fileB.get(line1++));

          // Lines following are trailing context, identical in fileA and fileB
          // The next change may overlap the context, so check and if so, form one hunk
          EGDiff.change nextChange = change.link;
          int nextChangeStart = fileA.size();
          if (nextChange != null)
            nextChangeStart = ((nextChange.line1 < nextChange.line0) ? nextChange.line1 : nextChange.line0);

          if (nextChangeStart - line0 > contextSize * 2) { // A separate hunk
            nextChangeStart = line0 + contextSize;
            hunkFinish = true;
          }
          if (nextChangeStart > fileA.size())
            nextChangeStart = fileA.size(); // Limit to file size
          while (line0 < nextChangeStart) {
            hunkLines.add(" " + fileA.get(line0++));
            line1++; // Keep in sync with trailing context
          }

          change = change.link;
        } while (!hunkFinish && change != null);

        int hunkStartB = contextStart + cumulExtraLinesBwrtA;
        int hunkTotA = line0 - contextStart;
        int hunkTotB = line1 - hunkStartB;

        hunkLines.add(headerPosn, "@@ -" + (contextStart + 1) + ',' + hunkTotA +
                        " +" + (hunkStartB + 1) + ',' + hunkTotB + " @@");
        cumulExtraLinesBwrtA += hunkTotB - hunkTotA;

      } while (change != null);

      return hunkLines;
    }
    return null;
  }

/* For testing:
  private static void printUniDiff(List<String> fileA, List<String> fileB, int contextSize) {
    List<String> uniDiff = generateUniDiff(fileA, fileB, contextSize);

    if (uniDiff != null)
      for (int j = 0; j < uniDiff.size(); j++)
        System.out.println(uniDiff.get(j));
  }
 */


  public static List<BlockDiff> diffLines(List<String> lines, List<String> reference) {
    List<BlockDiff> diffs = new ArrayList<BlockDiff>();

    EGDiff diff = new EGDiff(reference.toArray(), lines.toArray());
    EGDiff.change change = diff.diff_2(false);
    //printChange(change);
    //printUniDiff(reference, lines, 3);

    int l0 = 0, l1 = 0;
    while (change != null) {
      if (change.line0 > l0 && change.line1 > l1)
        diffs.add(new CopyBlock(l0, change.line0-l0));

      if (change.inserted != 0)
        diffs.add(new NewBlock(change.line1, lines.subList(change.line1, change.line1+change.inserted)));

      l0 = change.line0 + change.deleted;
      l1 = change.line1 + change.inserted;
      change = change.link;
    }

    if (l0 < reference.size())
      diffs.add(new CopyBlock(l0, reference.size()-l0));

    return diffs;
  }

  /** fills files with empty lines to align matching blocks
   *
   * @param file1 first file
   * @param file2 second file
   * @return an array with two lists
   */
  public static List<ExplodedLine> explode(List<String> file1, List<String> file2) {
    List<ExplodedLine> lines = new ArrayList<ExplodedLine>();
    List<BlockDiff> diffs = BlockDiffer.diffLines(file2, file1);
    int lastLineCopied = 0, rightOnlyStart = -1, rightPosition = 0;
    for (int i = 0; i < diffs.size(); i++) {
      BlockDiff diff = diffs.get(i);
      if (diff instanceof CopyBlock) {
        CopyBlock copyBlock = (CopyBlock) diff;
        if (lastLineCopied < copyBlock.getFirstLine()) {
          if (rightOnlyStart >= 0) {
            int overlap = Math.min(lines.size()-rightOnlyStart, copyBlock.getFirstLine()-lastLineCopied);
            //lines.subList(rightOnlyStart, rightOnlyStart+overlap).clear();
            convertRightOnlyToDifferent(lines, rightOnlyStart, overlap, file1, lastLineCopied);
            lastLineCopied += overlap;
          }
          addBlock(lines, LEFT_ONLY, file1, lastLineCopied, copyBlock.getFirstLine(), lastLineCopied, -1);
        }
        addBlock(lines, IDENTICAL, file1, copyBlock.getFirstLine(), copyBlock.getFirstLine()+copyBlock.getLines(),
          copyBlock.getFirstLine(), rightPosition);
        rightPosition += copyBlock.getLines();
        lastLineCopied = copyBlock.getFirstLine()+copyBlock.getLines();
        rightOnlyStart = -1;
      } else if (diff instanceof NewBlock) {
        NewBlock newBlock = (NewBlock) diff;
        /*if (nextDiff instanceof BlockDiffer.CopyBlock) {
          BlockDiffer.CopyBlock copyBlock = (BlockDiffer.CopyBlock) nextDiff;
          copyBlock.getFirstLine()-lastLineCopied*/
        rightOnlyStart = lines.size();
        addBlock(lines, RIGHT_ONLY, newBlock.getContents(), 0, newBlock.getContents().size(), -1, rightPosition);
        rightPosition += newBlock.getContents().size();
      }
    }

    if (rightOnlyStart >= 0) {
      int overlap = Math.min(lines.size()-rightOnlyStart, file1.size()-lastLineCopied);
      //lines.subList(rightOnlyStart, rightOnlyStart+overlap).clear();
      convertRightOnlyToDifferent(lines, rightOnlyStart, overlap, file1, lastLineCopied);
      lastLineCopied += overlap;
    }
    addBlock(lines, LEFT_ONLY, file1, lastLineCopied, file1.size(), lastLineCopied, -1);

    return lines;
  }

  private static void convertRightOnlyToDifferent(List<ExplodedLine> lines, int start, int numLines,
                                                  List<String> leftLines, int leftStart) {
    for (int i = 0; i < numLines; i++) {
      ExplodedLine line = lines.get(start+i);
      lines.set(start+i,
        new ExplodedLine(DIFFERENT, leftLines.get(i+leftStart), line.getRight(), i+leftStart, line.getRightIndex()));
    }
  }

  private static void addBlock(List<ExplodedLine> lines, int type, List<String> srcLines, int start, int end,
                               int leftStart, int rightStart) {
    for (int i = start; i < end; i++)
      lines.add(new ExplodedLine(type, type == RIGHT_ONLY ? "" : srcLines.get(i),
                                       type == LEFT_ONLY ? "" : srcLines.get(i),
                                       type == RIGHT_ONLY ? -1 : i - start + leftStart,
                                       type == LEFT_ONLY ? -1 : i - start + rightStart));
  }

  public static List<ExplodedLine> condense(List<ExplodedLine> lines) {
    List<ExplodedLine> result = new ArrayList<ExplodedLine>();
    for (Iterator<ExplodedLine> i = lines.iterator(); i.hasNext();) {
      ExplodedLine line = i.next();
      if (line.getType() == IDENTICAL) {
        if (result.isEmpty() || result.get(result.size()-1).getType() != IDENTICAL)
          result.add(new ExplodedLine(IDENTICAL, "[...]", "[...]", -1, -1));
      } else
        result.add(line);
    }
    return result;
  }
}static ThreadLocal<Boolean> DynamicObject_loading = new ThreadLocal();

static class DynamicObject {
  String className; // just the name, without the "main$"
  LinkedHashMap<String,Object> fieldValues = new LinkedHashMap();
  
  DynamicObject() {}
  // className = just the name, without the "main$"
  DynamicObject(String className) {
  this.className = className;}
}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 fsi(int i) { return formatSnippetID(unq(i)); }
  String fsi() { return fsi(0); }
  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)); }
}
static class PersistableThrowable {
  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;
  }
}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();
  }
}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);
  }
}

/**
 * A class to compare vectors of objects.  The result of comparison
 * is a list of <code>change</code> objects which form an
 * edit script.  The objects compared are traditionally lines
 * of text from two files.  Comparison options such as "ignore
 * whitespace" are implemented by modifying the <code>equals</code>
 * and <code>hashcode</code> methods for the objects compared.
 * <p/>
 * The basic algorithm is described in: </br>
 * "An O(ND) Difference Algorithm and its Variations", Eugene Myers,
 * Algorithmica Vol. 1 No. 2, 1986, p 251.
 * <p/>
 * This class outputs different results from GNU diff 1.15 on some
 * inputs.  Our results are actually better (smaller change list, smaller
 * total size of changes), but it would be nice to know why.  Perhaps
 * there is a memory overwrite bug in GNU diff 1.15.
 *
 * @author Stuart D. Gathman, translated from GNU diff 1.15
 *         Copyright (C) 2000  Business Management Systems, Inc.
 *         <p/>
 *         This program is free software; you can redistribute it and/or modify
 *         it under the terms of the GNU General Public License as published by
 *         the Free Software Foundation; either version 1, or (at your option)
 *         any later version.
 *         <p/>
 *         This program is distributed in the hope that it will be useful,
 *         but WITHOUT ANY WARRANTY; without even the implied warranty of
 *         MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *         GNU General Public License for more details.
 *         <p/>
 *         You should have received a copy of the <a href=COPYING.txt>
 *         GNU General Public License</a>
 *         along with this program; if not, write to the Free Software
 *         Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 */

static class EGDiff {

  /**
   * Prepare to find differences between two arrays.  Each element of
   * the arrays is translated to an "equivalence number" based on
   * the result of <code>equals</code>.  The original Object arrays
   * are no longer needed for computing the differences.  They will
   * be needed again later to print the results of the comparison as
   * an edit script, if desired.
   */
  public EGDiff(Object[] a, Object[] b) {
    Hashtable h = new Hashtable(a.length + b.length);
    filevec[0] = new file_data(a, h);
    filevec[1] = new file_data(b, h);
  }

  /**
   * 1 more than the maximum equivalence value used for this or its
   * sibling file.
   */
  private int equiv_max = 1;

  /**
   * When set to true, the comparison uses a heuristic to speed it up.
   * With this heuristic, for files with a constant small density
   * of changes, the algorithm is linear in the file size.
   */
  public boolean heuristic = false;

  /**
   * When set to true, the algorithm returns a guarranteed minimal
   * set of changes.  This makes things slower, sometimes much slower.
   */
  public boolean no_discards = false;

  private int[] xvec, yvec;	/* Vectors being compared. */
  private int[] fdiag;		/* Vector, indexed by diagonal, containing
				   the X coordinate of the point furthest
				   along the given diagonal in the forward
				   search of the edit matrix. */
  private int[] bdiag;		/* Vector, indexed by diagonal, containing
				   the X coordinate of the point furthest
				   along the given diagonal in the backward
				   search of the edit matrix. */
  private int fdiagoff, bdiagoff;
  private final file_data[] filevec = new file_data[2];
  private int cost;

  /**
   * Find the midpoint of the shortest edit script for a specified
   * portion of the two files.
   * <p/>
   * We scan from the beginnings of the files, and simultaneously from the ends,
   * doing a breadth-first search through the space of edit-sequence.
   * When the two searches meet, we have found the midpoint of the shortest
   * edit sequence.
   * <p/>
   * The value returned is the number of the diagonal on which the midpoint lies.
   * The diagonal number equals the number of inserted lines minus the number
   * of deleted lines (counting only lines before the midpoint).
   * The edit cost is stored into COST; this is the total number of
   * lines inserted or deleted (counting only lines before the midpoint).
   * <p/>
   * This function assumes that the first lines of the specified portions
   * of the two files do not match, and likewise that the last lines do not
   * match.  The caller must trim matching lines from the beginning and end
   * of the portions it is going to specify.
   * <p/>
   * Note that if we return the "wrong" diagonal value, or if
   * the value of bdiag at that diagonal is "wrong",
   * the worst this can do is cause suboptimal diff output.
   * It cannot cause incorrect diff output.
   */

  private int diag(int xoff, int xlim, int yoff, int ylim) {
    final int[] fd = fdiag;	// Give the compiler a chance.
    final int[] bd = bdiag;	// Additional help for the compiler.
    final int[] xv = xvec;		// Still more help for the compiler.
    final int[] yv = yvec;		// And more and more . . .
    final int dmin = xoff - ylim;	// Minimum valid diagonal.
    final int dmax = xlim - yoff;	// Maximum valid diagonal.
    final int fmid = xoff - yoff;	// Center diagonal of top-down search.
    final int bmid = xlim - ylim;	// Center diagonal of bottom-up search.
    int fmin = fmid, fmax = fmid;	// Limits of top-down search.
    int bmin = bmid, bmax = bmid;	// Limits of bottom-up search.
    /* True if southeast corner is on an odd
				     diagonal with respect to the northwest. */
    final boolean odd = (fmid - bmid & 1) != 0;

    fd[fdiagoff + fmid] = xoff;
    bd[bdiagoff + bmid] = xlim;

    for (int c = 1; ; ++c) {
      int d;			/* Active diagonal. */
      boolean big_snake = false;

      /* Extend the top-down search by an edit step in each diagonal. */
      if (fmin > dmin)
        fd[fdiagoff + --fmin - 1] = -1;
      else
        ++fmin;
      if (fmax < dmax)
        fd[fdiagoff + ++fmax + 1] = -1;
      else
        --fmax;
      for (d = fmax; d >= fmin; d -= 2) {
        int x, y, oldx, tlo = fd[fdiagoff + d - 1], thi = fd[fdiagoff + d + 1];

        if (tlo >= thi)
          x = tlo + 1;
        else
          x = thi;
        oldx = x;
        y = x - d;
        while (x < xlim && y < ylim && xv[x] == yv[y]) {
          ++x;
          ++y;
        }
        if (x - oldx > 20)
          big_snake = true;
        fd[fdiagoff + d] = x;
        if (odd && bmin <= d && d <= bmax && bd[bdiagoff + d] <= fd[fdiagoff + d]) {
          cost = 2 * c - 1;
          return d;
        }
      }

      /* Similar extend the bottom-up search. */
      if (bmin > dmin)
        bd[bdiagoff + --bmin - 1] = Integer.MAX_VALUE;
      else
        ++bmin;
      if (bmax < dmax)
        bd[bdiagoff + ++bmax + 1] = Integer.MAX_VALUE;
      else
        --bmax;
      for (d = bmax; d >= bmin; d -= 2) {
        int x, y, oldx, tlo = bd[bdiagoff + d - 1], thi = bd[bdiagoff + d + 1];

        if (tlo < thi)
          x = tlo;
        else
          x = thi - 1;
        oldx = x;
        y = x - d;
        while (x > xoff && y > yoff && xv[x - 1] == yv[y - 1]) {
          --x;
          --y;
        }
        if (oldx - x > 20)
          big_snake = true;
        bd[bdiagoff + d] = x;
        if (!odd && fmin <= d && d <= fmax && bd[bdiagoff + d] <= fd[fdiagoff + d]) {
          cost = 2 * c;
          return d;
        }
      }

      /* Heuristic: check occasionally for a diagonal that has made
         lots of progress compared with the edit distance.
         If we have any such, find the one that has made the most
         progress and return it as if it had succeeded.

         With this heuristic, for files with a constant small density
         of changes, the algorithm is linear in the file size.  */

      if (c > 200 && big_snake && heuristic) {
        int best = 0;
        int bestpos = -1;

        for (d = fmax; d >= fmin; d -= 2) {
          int dd = d - fmid;
          if ((fd[fdiagoff + d] - xoff) * 2 - dd > 12 * (c + (dd > 0 ? dd : -dd))) {
            if (fd[fdiagoff + d] * 2 - dd > best
              && fd[fdiagoff + d] - xoff > 20
              && fd[fdiagoff + d] - d - yoff > 20) {
              int k;
              int x = fd[fdiagoff + d];

              /* We have a good enough best diagonal;
                 now insist that it end with a significant snake.  */
              for (k = 1; k <= 20; k++)
                if (xvec[x - k] != yvec[x - d - k])
                  break;

              if (k == 21) {
                best = fd[fdiagoff + d] * 2 - dd;
                bestpos = d;
              }
            }
          }
        }
        if (best > 0) {
          cost = 2 * c - 1;
          return bestpos;
        }

        best = 0;
        for (d = bmax; d >= bmin; d -= 2) {
          int dd = d - bmid;
          if ((xlim - bd[bdiagoff + d]) * 2 + dd > 12 * (c + (dd > 0 ? dd : -dd))) {
            if ((xlim - bd[bdiagoff + d]) * 2 + dd > best
              && xlim - bd[bdiagoff + d] > 20
              && ylim - (bd[bdiagoff + d] - d) > 20) {
              /* We have a good enough best diagonal;
                 now insist that it end with a significant snake.  */
              int k;
              int x = bd[bdiagoff + d];

              for (k = 0; k < 20; k++)
                if (xvec[x + k] != yvec[x - d + k])
                  break;
              if (k == 20) {
                best = (xlim - bd[bdiagoff + d]) * 2 + dd;
                bestpos = d;
              }
            }
          }
        }
        if (best > 0) {
          cost = 2 * c - 1;
          return bestpos;
        }
      }
    }
  }

  /**
   * Compare in detail contiguous subsequences of the two files
   * which are known, as a whole, to match each other.
   * <p/>
   * The results are recorded in the vectors filevec[N].changed_flag, by
   * storing a 1 in the element for each line that is an insertion or deletion.
   * <p/>
   * The subsequence of file 0 is [XOFF, XLIM) and likewise for file 1.
   * <p/>
   * Note that XLIM, YLIM are exclusive bounds.
   * All line numbers are origin-0 and discarded lines are not counted.
   */

  private void compareseq(int xoff, int xlim, int yoff, int ylim) {
    /* Slide down the bottom initial diagonal. */
    while (xoff < xlim && yoff < ylim && xvec[xoff] == yvec[yoff]) {
      ++xoff;
      ++yoff;
    }
    /* Slide up the top initial diagonal. */
    while (xlim > xoff && ylim > yoff && xvec[xlim - 1] == yvec[ylim - 1]) {
      --xlim;
      --ylim;
    }
    
    /* Handle simple cases. */
    if (xoff == xlim)
      while (yoff < ylim)
        filevec[1].changed_flag[1 + filevec[1].realindexes[yoff++]] = true;
    else if (yoff == ylim)
      while (xoff < xlim)
        filevec[0].changed_flag[1 + filevec[0].realindexes[xoff++]] = true;
    else {
      /* Find a point of correspondence in the middle of the files.  */

      int d = diag(xoff, xlim, yoff, ylim);
      int c = cost;
      int b = bdiag[bdiagoff + d];

      if (c == 1) {
        /* This should be impossible, because it implies that
           one of the two subsequences is empty,
           and that case was handled above without calling `diag'.
           Let's verify that this is true.  */
        throw new IllegalArgumentException("Empty subsequence");
      } else {
        /* Use that point to split this problem into two subproblems.  */
        compareseq(xoff, b, yoff, b - d);
        /* This used to use f instead of b,
           but that is incorrect!
           It is not necessarily the case that diagonal d
           has a snake from b to f.  */
        compareseq(b, xlim, b - d, ylim);
      }
    }
  }

  /**
   * Discard lines from one file that have no matches in the other file.
   */

  private void discard_confusing_lines() {
    filevec[0].discard_confusing_lines(filevec[1]);
    filevec[1].discard_confusing_lines(filevec[0]);
  }

  private boolean inhibit = false;

  /**
   * Adjust inserts/deletes of blank lines to join changes
   * as much as possible.
   */

  private void shift_boundaries() {
    if (inhibit)
      return;
    filevec[0].shift_boundaries(filevec[1]);
    filevec[1].shift_boundaries(filevec[0]);
  }

  public interface ScriptBuilder {
    /**
     * Scan the tables of which lines are inserted and deleted,
     * producing an edit script.
     *
     * @param changed0 true for lines in first file which do not match 2nd
     * @param len0     number of lines in first file
     * @param changed1 true for lines in 2nd file which do not match 1st
     * @param len1     number of lines in 2nd file
     * @return a linked list of changes - or null
     */
    public change build_script(boolean[] changed0, int len0,
                               boolean[] changed1, int len1);
  }

  /**
   * Scan the tables of which lines are inserted and deleted,
   * producing an edit script in reverse order.
   */

  static class ReverseScript implements ScriptBuilder {
    public change build_script(final boolean[] changed0, int len0,
                               final boolean[] changed1, int len1) {
      change script = null;
      int i0 = 0, i1 = 0;
      while (i0 < len0 || i1 < len1) {
        if (changed0[1 + i0] || changed1[1 + i1]) {
          int line0 = i0, line1 = i1;

          /* Find # lines changed here in each file.  */
          while (changed0[1 + i0]) ++i0;
          while (changed1[1 + i1]) ++i1;

          /* Record this change.  */
          script = new change(line0, line1, i0 - line0, i1 - line1, script);
        }

        /* We have reached lines in the two files that match each other.  */
        i0++;
        i1++;
      }

      return script;
    }
  }

  static class ForwardScript implements ScriptBuilder {
    /**
     * Scan the tables of which lines are inserted and deleted,
     * producing an edit script in forward order.
     */
    public change build_script(final boolean[] changed0, int len0,
                               final boolean[] changed1, int len1) {
      change script = null;
      int i0 = len0, i1 = len1;

      while (i0 >= 0 || i1 >= 0) {
        if (changed0[i0] || changed1[i1]) {
          int line0 = i0, line1 = i1;

          /* Find # lines changed here in each file.  */
          while (changed0[i0]) --i0;
          while (changed1[i1]) --i1;

          /* Record this change.  */
          script = new change(i0, i1, line0 - i0, line1 - i1, script);
        }

        /* We have reached lines in the two files that match each other.  */
        i0--;
        i1--;
      }

      return script;
    }
  }

  /**
   * Standard ScriptBuilders.
   */
  public final static ScriptBuilder
    forwardScript = new ForwardScript(),
  reverseScript = new ReverseScript();

  /* Report the differences of two files.  DEPTH is the current directory
     depth. */
  public final change diff_2(final boolean reverse) {
    return diff(reverse ? reverseScript : forwardScript);
  }

  /**
   * Get the results of comparison as an edit script.  The script
   * is described by a list of changes.  The standard ScriptBuilder
   * implementations provide for forward and reverse edit scripts.
   * Alternate implementations could, for instance, list common elements
   * instead of differences.
   *
   * @param bld an object to build the script from change flags
   * @return the head of a list of changes
   */
  public change diff(final ScriptBuilder bld) {

    /* Some lines are obviously insertions or deletions
       because they don't match anything.  Detect them now,
       and avoid even thinking about them in the main comparison algorithm.  */

    discard_confusing_lines();

    /* Now do the main comparison algorithm, considering just the
       undiscarded lines.  */

    xvec = filevec[0].undiscarded;
    yvec = filevec[1].undiscarded;

    int diags =
      filevec[0].nondiscarded_lines + filevec[1].nondiscarded_lines + 3;
    fdiag = new int[diags];
    fdiagoff = filevec[1].nondiscarded_lines + 1;
    bdiag = new int[diags];
    bdiagoff = filevec[1].nondiscarded_lines + 1;

    compareseq(0, filevec[0].nondiscarded_lines,
      0, filevec[1].nondiscarded_lines);
    fdiag = null;
    bdiag = null;

    /* Modify the results slightly to make them prettier
       in cases where that can validly be done.  */

    shift_boundaries();

    /* Get the results of comparison in the form of a chain
       of `struct change's -- an edit script.  */
    return bld.build_script(filevec[0].changed_flag,
      filevec[0].buffered_lines,
      filevec[1].changed_flag,
      filevec[1].buffered_lines);

  }

  /**
   * The result of comparison is an "edit script": a chain of change objects.
   * Each change represents one place where some lines are deleted
   * and some are inserted.
   * <p/>
   * LINE0 and LINE1 are the first affected lines in the two files (origin 0).
   * DELETED is the number of lines deleted here from file 0.
   * INSERTED is the number of lines inserted here in file 1.
   * <p/>
   * If DELETED is 0 then LINE0 is the number of the line before
   * which the insertion was done; vice versa for INSERTED and LINE1.
   */

  public static class change {
    /**
     * Previous or next edit command.
     */
    public change link;
    /**
     * # lines of file 1 changed here.
     */
    public final int inserted;
    /**
     * # lines of file 0 changed here.
     */
    public final int deleted;
    /**
     * Line number of 1st deleted line.
     */
    public final int line0;
    /**
     * Line number of 1st inserted line.
     */
    public final int line1;

    /**
     * Cons an additional entry onto the front of an edit script OLD.
     * LINE0 and LINE1 are the first affected lines in the two files (origin 0).
     * DELETED is the number of lines deleted here from file 0.
     * INSERTED is the number of lines inserted here in file 1.
     * <p/>
     * If DELETED is 0 then LINE0 is the number of the line before
     * which the insertion was done; vice versa for INSERTED and LINE1.
     */
    public change(int line0, int line1, int deleted, int inserted, change old) {
      this.line0 = line0;
      this.line1 = line1;
      this.inserted = inserted;
      this.deleted = deleted;
      this.link = old;
      //System.err.println(line0+","+line1+","+inserted+","+deleted);
    }
  }

  /**
   * Data on one input file being compared.
   */

  class file_data {

    /**
     * Allocate changed array for the results of comparison.
     */
    void clear() {
      /* Allocate a flag for each line of each file, saying whether that line
	 is an insertion or deletion.
	 Allocate an extra element, always zero, at each end of each vector.
       */
      changed_flag = new boolean[buffered_lines + 2];
    }

    /**
     * Return equiv_count[I] as the number of lines in this file
     * that fall in equivalence class I.
     *
     * @return the array of equivalence class counts.
     */
    int[] equivCount() {
      int[] equiv_count = new int[equiv_max];
      for (int i = 0; i < buffered_lines; ++i)
        ++equiv_count[equivs[i]];
      return equiv_count;
    }

    /**
     * Discard lines that have no matches in another file.
     * <p/>
     * A line which is discarded will not be considered by the actual
     * comparison algorithm; it will be as if that line were not in the file.
     * The file's `realindexes' table maps virtual line numbers
     * (which don't count the discarded lines) into real line numbers;
     * this is how the actual comparison algorithm produces results
     * that are comprehensible when the discarded lines are counted.
     * <p/>
     * When we discard a line, we also mark it as a deletion or insertion
     * so that it will be printed in the output.
     *
     * @param f the other file
     */
    void discard_confusing_lines(file_data f) {
      clear();
      /* Set up table of which lines are going to be discarded. */
      final byte[] discarded = discardable(f.equivCount());

      /* Don't really discard the provisional lines except when they occur
         in a run of discardables, with nonprovisionals at the beginning
         and end.  */
      filterDiscards(discarded);

      /* Actually discard the lines. */
      discard(discarded);
    }

    /**
     * Mark to be discarded each line that matches no line of another file.
     * If a line matches many lines, mark it as provisionally discardable.
     *
     * @param counts The count of each equivalence number for the other file.
     * @return 0=nondiscardable, 1=discardable or 2=provisionally discardable
     *         for each line
     */

    private byte[] discardable(final int[] counts) {
      final int end = buffered_lines;
      final byte[] discards = new byte[end];
      final int[] equivs = this.equivs;
      int many = 5;
      int tem = end / 64;

      /* Multiply MANY by approximate square root of number of lines.
	 That is the threshold for provisionally discardable lines.  */
      while ((tem = tem >> 2) > 0)
        many *= 2;

      for (int i = 0; i < end; i++) {
        int nmatch;
        if (equivs[i] == 0)
          continue;
        nmatch = counts[equivs[i]];
        if (nmatch == 0)
          discards[i] = 1;
        else if (nmatch > many)
          discards[i] = 2;
      }
      return discards;
    }

    /**
     * Don't really discard the provisional lines except when they occur
     * in a run of discardables, with nonprovisionals at the beginning
     * and end.
     */

    private void filterDiscards(final byte[] discards) {
      final int end = buffered_lines;

      for (int i = 0; i < end; i++) {
        /* Cancel provisional discards not in middle of run of discards.  */
        if (discards[i] == 2)
          discards[i] = 0;
        else if (discards[i] != 0) {
          /* We have found a nonprovisional discard.  */
          int j;
          int length;
          int provisional = 0;

          /* Find end of this run of discardable lines.
             Count how many are provisionally discardable.  */
          for (j = i; j < end; j++) {
            if (discards[j] == 0)
              break;
            if (discards[j] == 2)
              ++provisional;
          }

          /* Cancel provisional discards at end, and shrink the run.  */
          while (j > i && discards[j - 1] == 2) {
            discards[--j] = 0;
            --provisional;
          }

          /* Now we have the length of a run of discardable lines
             whose first and last are not provisional.  */
          length = j - i;

          /* If 1/4 of the lines in the run are provisional,
             cancel discarding of all provisional lines in the run.  */
          if (provisional * 4 > length) {
            while (j > i)
              if (discards[--j] == 2)
                discards[j] = 0;
          } else {
            int consec;
            int minimum = 1;
            int tem = length / 4;

            /* MINIMUM is approximate square root of LENGTH/4.
               A subrun of two or more provisionals can stand
               when LENGTH is at least 16.
               A subrun of 4 or more can stand when LENGTH >= 64.  */
            while ((tem = tem >> 2) > 0)
              minimum *= 2;
            minimum++;

            /* Cancel any subrun of MINIMUM or more provisionals
               within the larger run.  */
            for (j = 0, consec = 0; j < length; j++)
              if (discards[i + j] != 2)
                consec = 0;
              else if (minimum == ++consec)
              /* Back up to start of subrun, to cancel it all.  */
                j -= consec;
              else if (minimum < consec)
                discards[i + j] = 0;

            /* Scan from beginning of run
               until we find 3 or more nonprovisionals in a row
               or until the first nonprovisional at least 8 lines in.
               Until that point, cancel any provisionals.  */
            for (j = 0, consec = 0; j < length; j++) {
              if (j >= 8 && discards[i + j] == 1)
                break;
              if (discards[i + j] == 2) {
                consec = 0;
                discards[i + j] = 0;
              } else if (discards[i + j] == 0)
                consec = 0;
              else
                consec++;
              if (consec == 3)
                break;
            }

            /* I advances to the last line of the run.  */
            i += length - 1;

            /* Same thing, from end.  */
            for (j = 0, consec = 0; j < length; j++) {
              if (j >= 8 && discards[i - j] == 1)
                break;
              if (discards[i - j] == 2) {
                consec = 0;
                discards[i - j] = 0;
              } else if (discards[i - j] == 0)
                consec = 0;
              else
                consec++;
              if (consec == 3)
                break;
            }
          }
        }
      }
    }

    /**
     * Actually discard the lines.
     *
     * @param discards flags lines to be discarded
     */
    private void discard(final byte[] discards) {
      final int end = buffered_lines;
      int j = 0;
      for (int i = 0; i < end; ++i)
        if (no_discards || discards[i] == 0) {
          undiscarded[j] = equivs[i];
          realindexes[j++] = i;
        } else
          changed_flag[1 + i] = true;
      nondiscarded_lines = j;
    }

    file_data(Object[] data, Hashtable h) {
      buffered_lines = data.length;

      equivs = new int[buffered_lines];
      undiscarded = new int[buffered_lines];
      realindexes = new int[buffered_lines];

      for (int i = 0; i < data.length; ++i) {
        Integer ir = (Integer) h.get(data[i]);
        if (ir == null)
          h.put(data[i], new Integer(equivs[i] = equiv_max++));
        else
          equivs[i] = ir.intValue();
      }
    }

    /**
     * Adjust inserts/deletes of blank lines to join changes
     * as much as possible.
     * <p/>
     * We do something when a run of changed lines include a blank
     * line at one end and have an excluded blank line at the other.
     * We are free to choose which blank line is included.
     * `compareseq' always chooses the one at the beginning,
     * but usually it is cleaner to consider the following blank line
     * to be the "change".  The only exception is if the preceding blank line
     * would join this change to other changes.
     *
     * @param f the file being compared against
     */

    void shift_boundaries(file_data f) {
      final boolean[] changed = changed_flag;
      final boolean[] other_changed = f.changed_flag;
      int i = 0;
      int j = 0;
      int i_end = buffered_lines;
      int preceding = -1;
      int other_preceding = -1;

      for (; ;) {
        int start, end, other_start;

        /* Scan forwards to find beginning of another run of changes.
           Also keep track of the corresponding point in the other file.  */

        while (i < i_end && !changed[1 + i]) {
          while (other_changed[1 + j++])
            /* Non-corresponding lines in the other file
               will count as the preceding batch of changes.  */
            other_preceding = j;
          i++;
        }

        if (i == i_end)
          break;

        start = i;
        other_start = j;

        for (; ;) {
          /* Now find the end of this run of changes.  */

          while (i < i_end && changed[1 + i]) i++;
          end = i;

          /* If the first changed line matches the following unchanged one,
       and this run does not follow right after a previous run,
       and there are no lines deleted from the other file here,
       then classify the first changed line as unchanged
       and the following line as changed in its place.  */

          /* You might ask, how could this run follow right after another?
       Only because the previous run was shifted here.  */

          if (end != i_end
            && equivs[start] == equivs[end]
            && !other_changed[1 + j]
            && end != i_end
            && !((preceding >= 0 && start == preceding)
            || (other_preceding >= 0
            && other_start == other_preceding))) {
            changed[1 + end] = true;
            changed[1 + start++] = false;
            ++i;
            /* Since one line-that-matches is now before this run
               instead of after, we must advance in the other file
               to keep in synch.  */
            ++j;
          } else
            break;
        }

        preceding = i;
        other_preceding = j;
      }
    }

    /**
     * Number of elements (lines) in this file.
     */
    final int buffered_lines;

    /**
     * Vector, indexed by line number, containing an equivalence code for
     * each line.  It is this vector that is actually compared with that
     * of another file to generate differences.
     */
    private final int[] equivs;

    /**
     * Vector, like the previous one except that
     * the elements for discarded lines have been squeezed out.
     */
    final int[] undiscarded;

    /**
     * Vector mapping virtual line numbers (not counting discarded lines)
     * to real ones (counting those lines).  Both are origin-0.
     */
    final int[] realindexes;

    /**
     * Total number of nondiscarded lines.
     */
    int nondiscarded_lines;

    /**
     * Array, indexed by real origin-1 line number,
     * containing true for a line that is an insertion or a deletion.
     * The results of comparison are stored here.
     */
    boolean[] changed_flag;

  }
}

static <A> Iterator<A> iterator(Iterable<A> c) {
  return c == null ? emptyIterator() : c.iterator();
}
static UnsupportedOperationException unsupportedOperation() {
  throw new UnsupportedOperationException();
}
static List<String> diff(Collection<String> a, Collection<String> b) {
  Set<String> set = asSet(b);
  List<String> l = new ArrayList();
  for (String s : a)
    if (!set.contains(s))
      l.add(s);
  return l;
}
static String fsi(String id) {
  return formatSnippetID(id);
}
static void change() {
  //mainConcepts.allChanged();
  // safe version for now cause function is sometimes included unnecessarily (e.g. by EGDiff)
  callOpt(getOptMC("mainConcepts"), "allChanged");
}
static String formatSnippetID(String id) {
  return "#" + parseSnippetID(id);
}

static String formatSnippetID(long id) {
  return "#" + id;
}
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 int hashCodeFor(Object a) {
  return a == null ? 0 : a.hashCode();
}


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 Object getOptMC(String field) {
  return getOpt(mc(), field);
}
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(Collection<A> l) {
  if (l instanceof Set) return (Set) l;
  HashSet<A> set = new HashSet();
  for (A o : l)
    if (o != null)
      set.add(o);
  return set;
}
public static long parseSnippetID(String snippetID) {
  long id = Long.parseLong(shortenSnippetID(snippetID));
  if (id == 0) throw fail("0 is not a snippet ID");
  return id;
}


static String[] dropLast(String[] a, int n) {
  n = Math.min(n, a.length);
  String[] b = new String[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 shortenSnippetID(String snippetID) {
  if (snippetID.startsWith("#"))
    snippetID = snippetID.substring(1);
  String httpBlaBla = "http://tinybrain.de/";
  if (snippetID.startsWith(httpBlaBla))
    snippetID = snippetID.substring(httpBlaBla.length());
  return "" + parseLong(snippetID);
}
static char lastChar(String s) {
  return empty(s) ? '\0' : s.charAt(l(s)-1);
}


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

static <A> List<A> subList(List<A> l, int startIndex, int endIndex) {
  startIndex = max(0, min(l(l), startIndex));
  endIndex = max(0, min(l(l), endIndex));
  if (startIndex > endIndex) return litlist();
  return l.subList(startIndex, endIndex);
}


static long parseLong(String s) {
  if (s == null) return 0;
  return Long.parseLong(dropSuffix("L", s));
}

static long parseLong(Object s) {
  return Long.parseLong((String) s);
}


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 String dropSuffix(String suffix, String s) {
  return s.endsWith(suffix) ? s.substring(0, l(s)-l(suffix)) : s;
}

}