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 {

static boolean doIt;

public static void main(final String[] args) throws Exception {
  if (eq(first(args), "doit")) doIt = true;
  thinAllProgramsBackups(doIt);
}
static boolean eq(Object a, Object b) {
  return a == null ? b == null : a == b || b != null && a.equals(b);
}


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

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

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



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

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

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


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



static void thinAllProgramsBackups(boolean doIt) {
  for (String progID : programsWithFiles())
    thinAProgramsBackups(progID, doIt);
}


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

static String str(char[] c) {
  return new String(c);
}
static boolean empty(Collection c) { return c == null || c.isEmpty(); }
static boolean empty(CharSequence s) { return s == null || s.length() == 0; }
static boolean empty(Map map) { return map == null || map.isEmpty(); }
static boolean empty(Object[] o) { return o == null || o.length == 0; }
static boolean empty(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; }



static boolean empty(File f) { return getFileSize(f) == 0; }
static List<String> programsWithFiles() {
  List<String> l = new ArrayList();
  for (File dir : listDirs(javaxDataDir())) { try {
    if (dir.getName().startsWith("#") && nempty(listFiles(dir)))
      l.add(fsI(dir.getName()));
  } catch (Throwable __e) { _handleException(__e); }}
  return l;
}
static void thinAProgramsBackups(String progID, boolean doIt) {
  List<File> files = new ArrayList();
  Map<File,Double> ageMap = new HashMap();
  
  Pattern pat = Pattern.compile("^(.*)\\.backup(20\\d\\d)(\\d\\d)(\\d\\d)-(\\d\\d)$");
  //print("Processing backups of program " + progID);
  File dir = programDir(progID);
  for (File f : listFilesNotDirs(dir, newFile(dir, "backups"))) {
    String s = f.getName();
    Matcher matcher = pat.matcher(s);
    { if (!(matcher.find())) continue; }
    String originalName = matcher.group(1);
    { if (!(eq(originalName, "concepts.structure.gz"))) continue; }
    //print("Found backup: " + sfu(matcherGroups(matcher)));
    int year = matcherInt(matcher, 2);
    int month = matcherInt(matcher, 3);
    int day = matcherInt(matcher, 4);
    int hour = matcherInt(matcher, 5);
    long time = timestampFromYMDH(year, month, day, hour);
    double age = ((now()-time)/1000.0/60/60/24);
    //print("Age: " + age + " days");
    ageMap.put(f, age);
    files.add(f);
  }
  
  int numDeleted = 0;
  sortByMap_inPlace(files, ageMap);
  double lastAge = -1;
  for (File f : files) {
    double age = ageMap.get(f);
    if (!thinAProgramsBackups_shouldKeep(age, lastAge)) {
      //print("Deleting: " + f);
      ++numDeleted;
      if (doIt) {
        print("Deleting: " + f);
        f.delete();
      }
    } else {
      print("Keeping: " + f);
      lastAge = age;
    }
  }
  if (numDeleted != 0)
    print((doIt ? "Deleted: " : "Would delete: ") + n(numDeleted, "file"));
}

// age = age in days
static boolean thinAProgramsBackups_shouldKeep(double age, double lastAge) {
  if (age <= 2) return true;
  if (age <= 31 && age >= lastAge+1) return true;
  if (age >= lastAge+7) return true;
  return false;
}


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

static long getFileSize(File f) {
  return f == null ? 0 : f.length();
}
static List<File> listDirs(File dir) {
  if (dir == null) return emptyList();
  File[] files = dir.listFiles();
  List<File> l = new ArrayList();
  if (files != null)
    for (File f : files)
      if (f.isDirectory())
        l.add(f);
  return l;
}

static List<File> listDirs(String dir) {
  return listDirs(newFile(dir));
}
static File javaxDataDir_dir; // can be set to work on different base dir

static File javaxDataDir() {
  return javaxDataDir_dir != null ? javaxDataDir_dir : new File(userHome(), "JavaX-Data");
}

static File javaxDataDir(String... subs) {
  return newFile(javaxDataDir(), subs);
}
static boolean nempty(Collection c) {
  return !empty(c);
}

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

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

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

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

static boolean nempty(Object o) { return !empty(o); }
static File[] listFiles(File dir) {
  File[] files = dir.listFiles();
  return files == null ? new File[0] : files;
}

static File[] listFiles(String dir) {
  return listFiles(new File(dir));
}
static String fsI(String id) {
  return formatSnippetID(id);
}

static String fsI(long id) {
  return formatSnippetID(id);
}
static volatile PersistableThrowable _handleException_lastException;
static List _handleException_onException = synchroList(ll("printStackTrace2"));

static void _handleException(Throwable e) {
  _handleException_lastException = persistableThrowable(e);
  
  Throwable e2 = innerException(e);
  if (e2.getClass() == RuntimeException.class && eq(e2.getMessage(), "Thread cancelled.") || e2 instanceof InterruptedException)
    return;
    
  for (Object f : cloneList(_handleException_onException)) try {
    callF(f, e);
  } catch (Throwable e3) {
    printStackTrace2(e3); // not using pcall here - it could lead to endless loops
  }
}

static File programDir_mine; // set this to relocate program's data

static File programDir() {
  return programDir(getProgramID());
}

static File programDir(String snippetID) {
  boolean me = sameSnippetID(snippetID, programID());
  if (programDir_mine != null && me)
    return programDir_mine;
  File dir = new File(javaxDataDir(), formatSnippetID(snippetID));
  if (me) {
    String c = caseID();
    if (nempty(c)) dir = newFile(dir, c);
  }
  return dir;
}

static File programDir(String snippetID, String subPath) {
  return new File(programDir(snippetID), subPath);
}
static List<File> listFilesNotDirs(String dir) {
  return listFilesOnly(dir);
}

static List<File> listFilesNotDirs(File... dirs) {
  return listFilesOnly(dirs);
}
static File newFile(File base, String... names) {
  for (String name : names) base = new File(base, name);
  return base;
}

static File newFile(String name) {
  return name == null ? null : new File(name);
}
static int matcherInt(Matcher m, int i) {
  return parseInt(m.group(i));
}
// month = 1 to 12
static long timestampFromYMDH(int y, int m, int d, int h) {
  return new GregorianCalendar(y, m-1, d, h, 0).getTimeInMillis();
}
static long now_virtualTime;
static long now() {
  return now_virtualTime != 0 ? now_virtualTime : System.currentTimeMillis();
}

static <A> List<A> sortByMap_inPlace(List<A> l, Map<A, ?> map) {
  sort(l, mapComparator(map));
  return l;
}


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

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

// in bytes - will cut to half that
static volatile int print_log_max = 1024*1024;
static volatile int local_log_max = 100*1024;
//static 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((endsWithLetterOrDigit(s) ? s + ": " : s) + o);
  return o;
}

// slightly overblown signature to return original object...
static <A> A print(A o) {
  ping_okInCleanUp();
  if (print_silent) return o;
  String s = 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)
    // We do need the general callF machinery here as print_byThread is sometimes shared between modules
    if (isFalse(
      
        f instanceof F1 ? ((F1) f).get(s) :
      
      callF(f, s))) return;
  

  print_raw(s);
}

static void print_raw(String s) {
  s = fixNewLines(s);
  // TODO if (print_maxLineLength != 0)
  Appendable loc = local_log;
  Appendable buf = print_log;
  int loc_max = print_log_max;
  if (buf != loc && buf != null) {
    print_append(buf, s, print_log_max);
    loc_max = local_log_max;
  }
  if (loc != null) 
    print_append(loc, s, loc_max);
  System.out.print(s);
}
static String n(long l, String name) {
  return l + " " + trim(l == 1 ? singular(name) : getPlural(name));
}

static String n(Collection l, String name) {
  return n(l(l), name);
}

static String n(Map m, String name) {
  return n(l(m), name);
}

static String n(Object[] a, String name) {
  return n(l(a), name);
}




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 RuntimeException asRuntimeException(Throwable t) {
  
  if (t instanceof Error)
    _handleError((Error) t);
  
  return t instanceof RuntimeException ? (RuntimeException) t : new RuntimeException(t);
}
static String getClassName(Object o) {
  return o == null ? "null" : o instanceof Class ? ((Class) o).getName() : o.getClass().getName();
}
static ArrayList emptyList() {
  return new ArrayList();
  //ret Collections.emptyList();
}

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

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

// get correct type at once
static <A> ArrayList<A> emptyList(Class<A> c) {
  return new ArrayList();
}
static String _userHome;
static String userHome() {
  if (_userHome == null) {
    if (isAndroid())
      _userHome = "/storage/sdcard0/";
    else
      _userHome = System.getProperty("user.home");
    //System.out.println("userHome: " + _userHome);
  }
  return _userHome;
}

static File userHome(String path) {
  return new File(userDir(), path);
}
static String formatSnippetID(String id) {
  return "#" + parseSnippetID(id);
}

static String formatSnippetID(long id) {
  return "#" + id;
}
static <A> List<A> synchroList() {
  return Collections.synchronizedList(new ArrayList<A>());
}

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

static <A> List<A> ll(A... a) {
  ArrayList l = new ArrayList(a.length);
  for (A x : a) l.add(x);
  return l;
}
static PersistableThrowable persistableThrowable(Throwable e) {
  return e == null ? null : new PersistableThrowable(e);
}
static Throwable innerException(Throwable e) {
  return getInnerException(e);
}
static <A> ArrayList<A> cloneList(Iterable<A> l) {
  return l instanceof Collection ? cloneList((Collection) l) : asList(l);
}

static <A> ArrayList<A> cloneList(Collection<A> l) {
  if (l == null) return new ArrayList();
  synchronized(collectionMutex(l)) {
    return new ArrayList<A>(l);
  }
}
static Map<Class, ArrayList<Method>> callF_cache = newDangerousWeakHashMap();


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



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





  static <A> void callF(VF1<A> f, A a) {
    if (f != 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;
}
static String programID;

static String getProgramID() {
  return nempty(programID) ? formatSnippetIDOpt(programID) : "?";
}


// TODO: ask JavaX instead
static String getProgramID(Class c) {
  String id = (String) getOpt(c, "programID");
  if (nempty(id))
    return formatSnippetID(id);
  return "?";
}


static String getProgramID(Object o) {
  return getProgramID(getMainClass(o));
}
static boolean sameSnippetID(String a, String b) {
  if (!isSnippetID(a) || !isSnippetID(b)) return false;
  return parseSnippetID(a) == parseSnippetID(b);
}
static String programID() {
  return getProgramID();
}

static String programID(Object o) {
  return getProgramID(o);
}
static volatile String caseID_caseID;

static String caseID() { return caseID_caseID; }

static void caseID(String id) {
  caseID_caseID = id;
}
static List<File> listFilesOnly(String dir) {
  return listFilesOnly(new File(dir));
}

static List<File> listFilesOnly(File... dirs) {
  return concatMap(rcurry("listFilesWithSuffix", ""), dirs);
}

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

static int parseInt(char c) {
  return Integer.parseInt(str(c));
}
static <T> void sort(T[] a, Comparator<? super T> c) {
  Arrays.sort(a, c);
}

static <T> void sort(T[] a) {
  Arrays.sort(a);
}

static <T> void sort(List<T> a, Comparator<? super T> c) {
  Collections.sort(a, c);
}

static void sort(List a) {
  Collections.sort(a);
}
static <A, B> Comparator<A> mapComparator(final Map<A, B> map) {
  return new Comparator<A>() {
    public int compare(A a, A b) {
      return cmp(map.get(a), map.get(b));
    }
  };
}
static boolean endsWithLetterOrDigit(String s) {
  return s != null && s.length() > 0 && Character.isLetterOrDigit(s.charAt(s.length()-1));
}
static void ping_okInCleanUp() {
  if (ping_pauseAll  || ping_anyActions )
    ping_impl(true);
}
static boolean isFalse(Object o) {
  return eq(false, o);
}
static String fixNewLines(String s) {
  int i = indexOf(s, '\r');
  if (i < 0) return s;
  int l = s.length();
  StringBuilder out = new StringBuilder(l);
  out.append(s, 0, i);
  for (; i < l; i++) {
    char c = s.charAt(i);
    if (c != '\r')
      out.append(c);
    else {
      out.append('\n');
      if (i+1 < l && s.charAt(i+1) == '\n') ++i;
    }
  }
  return out.toString();
}
static void print_append(Appendable _buf, String s, int max) { try {
  synchronized(_buf) {
    _buf.append(s);
    if (!(_buf instanceof StringBuilder)) return;
    StringBuilder buf = (StringBuilder) ( _buf);
    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);
    }
  }
} catch (Exception __e) { throw rethrow(__e); } }
static String trim(String s) { return s == null ? null : s.trim(); }
static String trim(StringBuilder buf) { return buf.toString().trim(); }
static String trim(StringBuffer buf) { return buf.toString().trim(); }
static Map<String, String> singular_specials = litmap(
  "children", "child", "images", "image", "chess", "chess");
  
static Set<String> singular_specials2 = litset("time", "machine", "line");

static String singular(String s) {
  if (s == null) return null;
  { String _a_352 = singular_specials.get(s); if (!empty(_a_352)) return _a_352; }
  //try answer hippoSingulars().get(lower(s));
  if (singular_specials2.contains(dropSuffix("s", afterLastSpace(s))))
    return dropSuffix("s", s);
  if (s.endsWith("ness")) return s;
  if (s.endsWith("ges")) return dropSuffix("s", s);
  if (endsWith(s, "bases")) return dropLast(s);
  s = dropSuffix("es", s);
  s = dropSuffix("s", s);
  return s;
}
static List<String> getPlural_specials = ll("sheep", "fish");

static String getPlural(String s) {
  if (containsIgnoreCase(getPlural_specials, s)) return s;
  if (ewic(s, "y")) return dropSuffixIgnoreCase("y", s) + "ies";
  if (ewic(s, "ss")) return s + "es";
  if (ewic(s, "s")) return s;
  return s + "s";
}
static int l(Object[] a) { return a == null ? 0 : a.length; }
static int l(boolean[] a) { return a == null ? 0 : a.length; }
static int l(byte[] a) { return a == null ? 0 : a.length; }
static int l(short[] a) { return a == null ? 0 : a.length; }
static int l(long[] a) { return a == null ? 0 : a.length; }
static int l(int[] a) { return a == null ? 0 : a.length; }
static int l(float[] a) { return a == null ? 0 : a.length; }
static int l(double[] a) { return a == null ? 0 : a.length; }
static int l(char[] a) { return a == null ? 0 : a.length; }
static int l(Collection c) { return c == null ? 0 : c.size(); }
static int l(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)
    : o instanceof Object[] ? l((Object[]) o)
    : o instanceof boolean[] ? l((boolean[]) o)
    : o instanceof byte[] ? l((byte[]) o)
    : o instanceof char[] ? l((char[]) o)
    : o instanceof short[] ? l((short[]) o)
    : o instanceof int[] ? l((int[]) o)
    : o instanceof float[] ? l((float[]) o)
    : o instanceof double[] ? l((double[]) o)
    : o instanceof long[] ? l((long[]) o)
    : (Integer) call(o, "size");
}






static List<File> listFilesWithSuffix(File dir, String suffix) {
  List<File> l = new ArrayList();
  for (File f : listFiles(dir))
    if (!f.isDirectory() && (empty(suffix) || endsWithIgnoreCase(f.getName(), suffix)))
      l.add(f);
  return l;
}
static String getStackTrace2(Throwable e) {
  return hideCredentials(getStackTrace(unwrapTrivialExceptionWraps(e)) + replacePrefix("java.lang.RuntimeException: ", "FAIL: ",
    hideCredentials(str(innerException2(e)))) + "\n");
}
static void _handleError(Error e) {
  call(javax(), "_handleError", e);
}
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 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 File userDir() {
  return new File(userHome());
}

static File userDir(String path) {
  return new File(userHome(), path);
}
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 Throwable getInnerException(Throwable e) {
  if (e == null) return null;
  while (e.getCause() != null)
    e = e.getCause();
  return e;
}

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

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

static ArrayList<Float> asList(float[] a) {
  if (a == null) return null;
  ArrayList<Float> l = emptyList(a.length);
  for (float i : a) l.add(i);
  return l;
}
static <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 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 <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 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 Object invokeMethod(Method m, Object o, Object... args) { try {
  try {
    return m.invoke(o, args);
  } catch (InvocationTargetException e) {
    throw rethrow(getExceptionCause(e));
  } catch (IllegalArgumentException e) {
    throw new IllegalArgumentException(e.getMessage() + " - was calling: " + m + ", args: " + joinWithSpace(classNames(args)));
  }
} catch (Exception __e) { throw rethrow(__e); } }
static boolean call_checkArgs(Method m, Object[] args, boolean debug) {
  Class<?>[] types = m.getParameterTypes();
  if (types.length != 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 RuntimeException rethrow(Throwable t) {
  
  if (t instanceof Error)
    _handleError((Error) t);
  
  throw t instanceof RuntimeException ? (RuntimeException) t : new RuntimeException(t);
}
static String formatSnippetIDOpt(String s) {
  return isSnippetID(s) ? formatSnippetID(s) : s;
}
static <A> A getOpt(Object o, String field) {
  return (A) 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 rethrow(__e); } }

// access of static fields is not yet optimized
static <A> A 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 (A) f.get(null);
} catch (Exception __e) { throw rethrow(__e); } }

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

static Class getMainClass() {
  return mc();
}

static Class getMainClass(Object o) { try {
  if (o == null) return null;
  if (o instanceof Class && eq(((Class) o).getName(), "x30")) return (Class) o;
  return (o instanceof Class ? (Class) o : o.getClass()).getClassLoader().loadClass("main");
} catch (Exception __e) { throw rethrow(__e); } }
  public static boolean isSnippetID(String s) {
    try {
      parseSnippetID(s);
      return true;
    } catch (RuntimeException e) {
      return false;
    }
  }
// f must return a list
static List concatMap(Object f, Iterable l) {
  return concatLists(map(f, l));
}

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

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

static List concatMap(Object[] l, Object f) {
  return concatMap(f, l);
}
static Object rcurry(final Object f, final Object arg) {
  int n = numberOfFunctionArguments(f);
  if (n == 0) throw fail("function takes no arguments");
  if (n == 1) return new F0() {
    Object get() {
      return callF(f, arg);
    }
  };
  if (n == 2)
    return new F1() {
      Object get(Object a) {
        return callF(f, a, arg);
      }
    };
  throw todo("currying a function with " + n + "arguments");
}
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(Object a, Object b) {
  if (a == null) return b == null ? 0 : -1;
  if (b == null) return 1;
  return ((Comparable) a).compareTo(b);
}
//sbool ping_actions_shareable = true;
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();
static ThreadLocal<Boolean> ping_isCleanUpThread = new ThreadLocal();


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

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

static void litmap_impl(Map map, Object... x) {
  for (int i = 0; i < x.length-1; i += 2)
    if (x[i+1] != null)
      map.put(x[i], x[i+1]);
}
static <A> HashSet<A> litset(A... items) {
  return lithashset(items);
}
static String dropSuffix(String suffix, String s) {
  return s.endsWith(suffix) ? s.substring(0, l(s)-l(suffix)) : s;
}
static String afterLastSpace(String s) {
  return s == null ? null : substring(s, s.lastIndexOf(' ')+1);
}
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 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 boolean containsIgnoreCase(Collection<String> l, String s) {
  if (l != null) for (String x : l)
    if (eqic(x, s))
      return true;
  return false;
}

static boolean containsIgnoreCase(String[] l, String s) {
  if (l != null) for (String x : l)
    if (eqic(x, s))
      return true;
  return false;
}

static boolean containsIgnoreCase(String s, char c) {
  return indexOfIgnoreCase(s, String.valueOf(c)) >= 0;
}

static boolean containsIgnoreCase(String a, String b) {
  return indexOfIgnoreCase(a, b) >= 0;
}
static boolean ewic(String a, String b) {
  return endsWithIgnoreCase(a, b);
}


static String dropSuffixIgnoreCase(String suffix, String s) {
  return ewic(s, suffix) ? s.substring(0, l(s)-l(suffix)) : s;
}
static <A> A call(Object o) {
  return (A) callF(o);
}

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

static <A> A call(Object o, String method, Object... args) {
  return (A) call_cached(o, method, args);
}


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 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 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 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 String replacePrefix(String prefix, String replacement, String s) {
  if (!startsWith(s, prefix)) return s;
  return replacement + substring(s, l(prefix));
}
static Throwable innerException2(Throwable e) {
  if (e == null) return null;
  while (empty(e.getMessage()) && e.getCause() != null)
    e = e.getCause();
  return e;
}
static Class javax() {
  return getJavaX();
}
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 Throwable getException(Runnable r) {
  try {
    callF(r);
    return null;
  } catch (Throwable e) {
    return e;
  }
}
static String className(Object o) {
  return getClassName(o);
}
// get purpose 1: access a list/array/map (safer version of x.get(y))

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

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

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

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

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

static Object get(Object o, String field) {
  try {
    if (o == null) return null;
    if (o instanceof Class) return get((Class) o, field);
    
    if (o instanceof Map)
      return ((Map) o).get(field);
      
    Field f = getOpt_findField(o.getClass(), field);
    if (f != null) {
      f.setAccessible(true);
      return f.get(o);
    }
      
    
  } 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 boolean eqOneOf(Object o, Object... l) {
  for (Object x : l) if (eq(o, x)) return true; return false;
}
static List<Pair> _registerDangerousWeakMap_preList;

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

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

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

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


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

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

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

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


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

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


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

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

// map: func(key, value) -> list element
static List map(Map map, Object f) {
  List x = new ArrayList();
  if (map != null) for (Object _e : map.entrySet()) {
    Map.Entry e = (Map.Entry) _e;
    x.add(callF(f, e.getKey(), e.getValue()));
  }
  return x;
}
static int numberOfFunctionArguments(Object f) {
   if (f instanceof F0) return 0; 
   if (f instanceof F1) return 1; 
  
   if (f instanceof VF1) return 1; 
  
  
  if (f instanceof String) return numberOfMethodArguments(mc(), (String) f);
  return numberOfMethodArguments(f, "get");
}
  static RuntimeException todo() {
    throw new RuntimeException("TODO");
  }
  
  static RuntimeException todo(String msg) {
    throw new RuntimeException("TODO: " + msg);
  }
static <A, B> Map<A, B> newWeakHashMap() {
  return _registerWeakMap(synchroMap(new WeakHashMap()));
}
// TODO: test if android complains about this
static boolean isAWTThread() {
  if (isAndroid()) return false;
  if (isHeadless()) return false;
  return isAWTThread_awt();
}

static boolean isAWTThread_awt() {
  return SwingUtilities.isEventDispatchThread();
}
static boolean isTrue(Object o) {
  if (o instanceof Boolean)
    return ((Boolean) o).booleanValue();
  if (o == null) return false;
  if (o instanceof ThreadLocal)
    return isTrue(((ThreadLocal) o).get());
  throw fail(getClassName(o));
}
static void failIfUnlicensed() {
  assertTrue("license off", licensed());
}
static Thread currentThread() {
  return Thread.currentThread();
}
static <A> HashSet<A> lithashset(A... items) {
  HashSet<A> set = new HashSet();
  for (A a : items) set.add(a);
  return set;
}
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 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) {
  if (l == null) return null;
  startIndex = Math.max(0, startIndex);
  endIndex = Math.min(l(l), endIndex);
  if (startIndex >= endIndex) return ll();
  return l.subList(startIndex, endIndex);
}


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



static boolean eqic(char a, char b) {
  if (a == b) return true;
  
    char u1 = Character.toUpperCase(a);
    char u2 = Character.toUpperCase(b);
    if (u1 == u2) return true;
  
  return Character.toLowerCase(u1) == Character.toLowerCase(u2);
}
// works on lists and strings and null

static int indexOfIgnoreCase(List<String> a, String b) {
  return indexOfIgnoreCase(a, b, 0);
}

static int indexOfIgnoreCase(List<String> a, String b, int i) {
  int n = l(a);
  for (; i < n; i++)
    if (eqic(a.get(i), b)) return i;
  return -1;
}

static int indexOfIgnoreCase(String a, String b) {
  return indexOfIgnoreCase_manual(a, b);
  /*Matcher m = Pattern.compile(b, Pattern.CASE_INSENSITIVE + Pattern.LITERAL).matcher(a);
  if (m.find()) return m.start(); else ret -1;*/
}
static Object call_cached(Object o, String method, Object... args) { try {
  if (o == null) return null;
  
  if (o instanceof Class) {
    Class c = (Class) o;
    _MethodCache cache = callOpt_getCache(c);
    
    // TODO: (super-rare) case where method exists static and non-static
    // with different args
    
    Method me = cache.findMethod(method, args);
    if (me == null)
      throw fail("Method " + c.getName() + "." + method + "(" + joinWithComma(classNames(args)) + ") not found");
    if ((me.getModifiers() & Modifier.STATIC) == 0)
      throw fail("Method " + c.getName() + "." + method + "(" + joinWithComma(classNames(args)) + ") not static");
    return invokeMethod(me, null, args);
  } else {
    Class c = o.getClass();
    _MethodCache cache = callOpt_getCache(c);

    Method me = cache.findMethod(method, args);
    if (me == null)
      throw fail("Method " + c.getName() + "." + method + "(" + joinWithComma(classNames(args)) + ") not found");
    return invokeMethod(me, o, args);
  }
} catch (Exception __e) { throw rethrow(__e); } }


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

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

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

static _MethodCache callOpt_getCache(Class c) {
  synchronized(callOpt_cache) {
    _MethodCache cache = callOpt_cache.get(c);
    if (cache == null)
      callOpt_cache.put(c, cache = new _MethodCache(c));
    return cache;
  }
}
static boolean regionMatchesIC(String a, int offsetA, String b, int offsetB, int len) {
  
  
    return a != null && a.regionMatches(true, offsetA, b, offsetB, len);
  
}
// 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 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(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;
}


static Class __javax;

static Class getJavaX() { try {
  
  return __javax;
} catch (Exception __e) { throw rethrow(__e); } }
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 <A, B> Pair<A, B> pair(A a, B b) {
  return new Pair(a, b);
}

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

static <A> A assertNotNull(String msg, A a) {
  assertTrue(msg, a != null);
  return a;
}
static Map synchroHashMap() {
  return Collections.synchronizedMap(new HashMap());
}

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

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

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

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

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


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

static void clear(Collection c) {
  if (c != null) c.clear();
}
static <A, B> void put(Map<A, B> map, A a, B b) {
  if (map != null) map.put(a, b);
}
static boolean isSubtypeOf(Class a, Class b) {
  return b.isAssignableFrom(a); // << always hated that method, let's replace it!
}
static int numberOfMethodArguments(Object o, String method) {
  Class c;
  boolean mustBeStatic = false;
  if (o instanceof Class) {
    c = (Class) o;
    mustBeStatic = true;
  } else
    c = o.getClass();
      
  Class _c = c;
  int n = -1;
  while (c != null) {
    for (Method m : c.getDeclaredMethods()) {
      if (!m.getName().equals(method)) continue;
      if (mustBeStatic && !methodIsStatic(m)) continue;
      int nn = l(m.getParameterTypes());
      if (n == -1) n = nn;
      else if (n != nn) throw fail("Variable number of method arguments: " + _c + "." + method);
    }
    c = c.getSuperclass();
  }
  if (n == -1) throw fail("Method not found: " + _c + "." + method);
  return n;
}
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 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 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 volatile boolean licensed_yes = true;

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

static void licensed_off() {
  licensed_yes = false;
}
static String asString(Object o) {
  return o == null ? null : o.toString();
}
static int indexOfIgnoreCase_manual(String a, String b) {
  int la = l(a), lb = l(b);
  if (la < lb) return -1;
  int n = la-lb;
  
  loop: for (int i = 0; i <= n; i++) {
    for (int j = 0; j < lb; j++) {
      char c1 = a.charAt(i+j), c2 = b.charAt(j);
      if (!eqic(c1, c2))
        continue loop;
    }
    return i;
  }
  return -1;
}
static String joinWithComma(Collection<String> c) {
  return join(", ", c);
}

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


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



static boolean neq(Object a, Object b) {
  return !eq(a, b);
}
static boolean methodIsStatic(Method m) {
  return (m.getModifiers() & Modifier.STATIC) != 0;
}
static void printException(Throwable e) {
  printStackTrace(e);
}


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));
}


// immutable, has strong refs
final static class _MethodCache {
  final Class c;
  final HashMap<String, List<Method>> cache = new HashMap();
  
  _MethodCache(Class c) {
  this.c = c;
    _init();
  }
  
  void _init() {
    Class _c = c;
    while (_c != null) {
      for (Method m : _c.getDeclaredMethods()) {
        m.setAccessible(true);
        multiMapPut(cache, m.getName(), m);
      }
      _c = _c.getSuperclass();
    }
    
  }

  // Returns only matching methods
  Method findMethod(String method, Object[] args) { try {
    List<Method> m = cache.get(method);
    
    if (m == null) return null;
    int n = m.size();
    for (int i = 0; i < n; i++) {
      Method me = m.get(i);
      if (call_checkArgs(me, args, false))
        return me;
    }
    return null;
  } catch (Exception __e) { throw rethrow(__e); } }
}static abstract class VF1<A> {
  abstract void get(A a);
}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);
}static class Pair<A, B> implements Comparable<Pair<A, B>> {
  A a;
  B b;

  Pair() {}
  Pair(A a, B b) {
  this.b = b;
  this.a = a;}
  
  public int hashCode() {
    return hashCodeFor(a) + 2*hashCodeFor(b);
  }
  
  public boolean equals(Object o) {
    if (o == this) return true;
    if (!(o instanceof Pair)) return false;
    Pair t = (Pair) o;
    return eq(a, t.a) && eq(b, t.b);
  }
  
  public String toString() {
    return "<" + a + ", " + b + ">";
  }
  
  public int compareTo(Pair<A, B> p) {
    if (p == null) return 1;
    int i = ((Comparable<A>) a).compareTo(p.a);
    if (i != 0) return i;
    return ((Comparable<B>) b).compareTo(p.b);
  }
}

  static Method findMethod(Object o, String method, Object... args) {
    try {
      if (o == null) return null;
      if (o instanceof Class) {
        Method m = findMethod_static((Class) o, method, args, false);
        if (m == null) return null;
        m.setAccessible(true);
        return m;
      } else {
        Method m = findMethod_instance(o, method, args, false);
        if (m == null) return null;
        m.setAccessible(true);
        return m;
      }
    } catch (Exception e) {
      throw new RuntimeException(e);
    }
  }

  static Method findMethod_static(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() & Modifier.STATIC) == 0 || !findMethod_checkArgs(m, args, debug))
          continue;

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

  static Method findMethod_instance(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) && findMethod_checkArgs(m, args, debug))
          return m;
      }
      c = c.getSuperclass();
    }
    return null;
  }

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


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

}