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 {
  Symbol a = symbol("abc");
  gc();
  Symbol b = symbol("ABC");
  Symbol c = symbol("def");
  assertEqualsVerbose("abc", str(a));
  assertEqualsVerbose("ABC", str(b));
  assertEqualsVerbose("def", str(c));
  assertEqualsVerbose(a, a);
  assertEqualsVerbose(a, b);
  assertNotEqualsVerbose(a, c);
  assertEqualsVerbose(a.hashCode(), b.hashCode());
  print(c.hashCode());
  if (c.hashCode() == a.hashCode()) print("weird. fluke?"); else print("OK");
}
static String str(Object o) {
  return o == null ? "null" : o.toString();
}

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


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

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



static Symbol symbol(String s) {
  
  
  if (s == null) return null;
  synchronized(symbol_map) {
    // This is a trick that works because of how WeakHashMap compares keys.
    MasterSymbol master = new MasterSymbol(s, true);
    MasterSymbol existingMaster = masterSymbol_map.findKey(master);
    if (existingMaster == null)
      masterSymbol_map.put(existingMaster = master, true);
    
    
    // directly return master if exact match
    boolean isEq = eq(s, existingMaster.text);
    if (isEq) return existingMaster;
    
    // second lookup after master found
    Symbol symbol = new Symbol(s, existingMaster);
    Symbol existingSymbol = symbol_map.findKey(symbol);
    if (existingSymbol == null)
      symbol_map.put(existingSymbol = symbol, true);
    
      
    return existingSymbol;
  }
  
}

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

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

// 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) {
  
  if (print_byThread != null) {
    Object f = print_byThread.get();
    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(long l) {
  print(String.valueOf(l));
}

static void print(char c) {
  print(String.valueOf(c));
}

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 void assertNotEqualsVerbose(Object x, Object y) {
  assertNotEqualsVerbose((String) null, x, y);
}

static void assertNotEqualsVerbose(String msg, Object x, Object y) {
  if (eq(x, y))
    throw fail((msg != null ? msg + ": " : "") + sfu(x));
  else
    print("OK: " + sfu(y) + " != " + sfu(x));
}
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))
    throw fail((msg != null ? msg + ": " : "") + sfu(y) + " != " + sfu(x));
  else
    print("OK: " + sfu(x));
}


static volatile long gc_memoryUsedAfterGC;

static void gc() {
  callOpt(javax(), "cleanWeakMaps");
  System.gc();
  gc_memoryUsedAfterGC = usedMemory();
}


static String fixNewLines(String s) {
  return s.replace("\r\n", "\n").replace("\r", "\n");
}
static long usedMemory() {
  return Runtime.getRuntime().totalMemory()-Runtime.getRuntime().freeMemory();
}
static String sfu(Object o) { return structureForUser(o); }
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 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 m.invoke(null, args);
    } else {
      Method m = callOpt_findMethod(o, method, args, false);
      if (m == null) return null;
      m.setAccessible(true);
      return m.invoke(o, args);
    }
  } catch (Exception e) {
    //fail(e.getMessage() + " | Method: " + method + ", receiver: " + className(o) + ", args: (" + join(", ", map(f className, args) + ")");
    throw new RuntimeException(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 WeakHashMap<Class, ArrayList<Method>> callF_cache = new WeakHashMap();




  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 methods.get(0).invoke(f, args);
  for (int i = 0; i < n; i++) {
    Method m = methods.get(i);
    if (call_checkArgs(m, args, false))
      return m.invoke(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 boolean isFalse(Object o) {
  return eq(false, 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);
}

// a little kludge for stuff like eq(symbol, "$X")

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

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 Class javax() {
  return getJavaX();
}


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

static <A, B> Map<A, B> synchroMap(Map<A, B> map) {
  return Collections.synchronizedMap(map);
}
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 me.invoke(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 me.invoke(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 me.invoke(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 RuntimeException asRuntimeException(Throwable t) {
  
  if (t instanceof Error)
    _handleError((Error) t);
  
  return t instanceof RuntimeException ? (RuntimeException) t : new RuntimeException(t);
}
static String structureForUser(Object o) {
  return beautifyStructure(struct_noStringSharing(o));
}
// 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 e) {
  throw asRuntimeException(e);
}
// 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 Class __javax;

static Class getJavaX() {
  return __javax;
}
static Thread currentThread() {
  return Thread.currentThread();
}
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 instanceof String ? l((String) o)
    : o instanceof Map ? l((Map) o)
    : l((Collection) o); // incomplete
}




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 instanceof Class) {
      Method m = call_findStaticMethod((Class) o, method, args, false);
      m.setAccessible(true);
      return m.invoke(null, args);
    } else {
      Method m = call_findMethod(o, method, args, false);
      m.setAccessible(true);
      return m.invoke(o, args);
    }
  } catch (Exception e) {
    throw e instanceof RuntimeException ? (RuntimeException) e : new RuntimeException(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 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 getClassName(Object o) {
  return o == null ? "null" : o instanceof Class ? ((Class) o).getName() : o.getClass().getName();
}


static String beautifyStructure(String s) {
  return structure_addTokenMarkers(s);
}
static Boolean isHeadless_cache;

static boolean isHeadless() {
  if (isHeadless_cache != null) return isHeadless_cache;
  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 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 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 <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);
}

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 void printException(Throwable e) {
  printStackTrace(e);
}
static Map synchroHashMap() {
  return Collections.synchronizedMap(new HashMap());
}

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 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 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 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 List<String> getClassNames(Collection l) {
  List<String> out = new ArrayList();
  if (l != null) for (Object o : l)
    out.add(o == null ? null : getClassName(o));
  return out;
}
static boolean 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 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");
      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 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 void printStackTrace2(S indent, Throwable e) {
  if (endsWithLetter(indent)) indent += " ";
  printIndent(indent, getStackTrace2(e));
}*/


static Iterator emptyIterator() {
  return Collections.emptyIterator();
}
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 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 == 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; }
  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 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
      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 getStackTrace(Throwable throwable) {
  lastException(throwable);
  StringWriter writer = new StringWriter();
  throwable.printStackTrace(new PrintWriter(writer));
  return hideCredentials(writer.toString());
}
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 getStackTrace2(Throwable throwable) {
  return hideCredentials(getStackTrace(throwable) + replacePrefix("java.lang.RuntimeException: ", "FAIL: ",
    hideCredentials(str(getInnerException(throwable)))) + "\n");
}
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
      out.print(c);
  }
  out.print('"');
}
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;
}
// replacement for class JavaTok
// maybe incomplete, might want to add floating point numbers
// todo also: extended multi-line strings

static int javaTok_n, javaTok_elements;
static boolean javaTok_opt;

static List<String> javaTok(String s) {
  return javaTok(s, null);
}

static List<String> javaTok(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 && javaTok_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 && javaTok_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 List<String> javaTok(List<String> tok) {
  return javaTok(join(tok), tok);
}

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

static boolean nempty(Iterator i) {
  return i != null && i.hasNext();
}
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 int parseInt(String s) {
  return empty(s) ? 0 : Integer.parseInt(s);
}

static int parseInt(char c) {
  return Integer.parseInt(str(c));
}
static HashMap<Class, Field[]> getDeclaredFields_cache = new HashMap();

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 <A> A popLast(List<A> l) {
  return liftLast(l);
}
static String boolArrayToHex(boolean[] a) {
  return bytesToHex(boolArrayToBytes(a));
}
static boolean endsWithLetterOrDigit(String s) {
  return nempty(s) && isLetterOrDigit(lastCharacter(s));
}
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 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 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 volatile Throwable lastException_lastException;

static Throwable lastException() {
  return lastException_lastException;
}

static void lastException(Throwable e) {
  lastException_lastException = 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 String hideCredentials(URL url) { return url == null ? null : hideCredentials(str(url)); }

static String hideCredentials(String url) {
  return url.replaceAll("([&?])_pass=[^&\\s\"]*", "$1_pass=<hidden>");
}
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 boolean neq(Object a, Object b) {
  return !eq(a, b);
}
static boolean isLetterOrDigit(char c) {
  return Character.isLetterOrDigit(c);
}
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(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 int lastIndexOf(String a, String b) {
  return a == null || b == null ? -1 : a.lastIndexOf(b);
}


static interface Hasher<A> {
  int hashCode(A a);
  boolean equals(A a, A b);
}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 Symbol implements CharSequence, Comparable<Symbol> {
  String text;
  MasterSymbol master;
  
  Symbol() {}
  Symbol(String text, boolean dummy) {
  this.text = text;} // weird signature to prevent accidental calling
  Symbol(String text, MasterSymbol master) {
  this.master = master;
  this.text = text;}
  
  boolean isMaster() { return master == this; }
  public int hashCode() { return master.lowerCaseHash; }
  String text() { return text; }
  public String toString() { return text; }
  String lowerCase() { return lower(text()); }
  public boolean equals(Object o) {
    if (!(o instanceof Symbol)) return false;
    boolean result = o instanceof Symbol && master == ((Symbol) o).master;
    
    return result;
  }
  
  public int length() { return text.length(); }
  public char charAt(int index) { return text.charAt(index); }
  public CharSequence subSequence(int start, int end) {
    return text.substring(start, end);
  }
  
  // This really has to be correct for TreeMap<Symbol, ...>
  // equals() <=> compareTo() == 0 or at least
  // equals() => compareTo() == 0.
  public int compareTo(Symbol s) {
    return lowerCase().compareTo(s.lowerCase());
  }
}

static final class MasterSymbol extends Symbol {
  //S lowerCase;
  int lowerCaseHash;
  boolean dollarVar;
  
  MasterSymbol() {}
  MasterSymbol(String text, boolean dummy) {
  this.text = text;
    master = this;
    String lowerCase = lower(text);
    lowerCaseHash = lowerCase.hashCode();
    dollarVar = isDollarVar(lowerCase);
  }
  
  int lowerCaseHash() { return lowerCaseHash; }
}/*
 * @(#)WeakHashMap.java	1.5 98/09/30
 *
 * Copyright 1998 by Sun Microsystems, Inc.,
 * 901 San Antonio Road, Palo Alto, California, 94303, U.S.A.
 * All rights reserved.
 *
 * This software is the confidential and proprietary information
 * of Sun Microsystems, Inc. ("Confidential Information").  You
 * shall not disclose such Confidential Information and shall use
 * it only in accordance with the terms of the license agreement
 * you entered into with Sun.
 */
 
// From https://github.com/mernst/plume-lib/blob/df0bfafc3c16848d88f4ea0ef3c8bf3367ae085e/java/src/plume/WeakHasherMap.java

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

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

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

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

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

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

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

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

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

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

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

    }


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

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


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


    /* -- Constructors -- */

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

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

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

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


    /* -- Simple queries -- */

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

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

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

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

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

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

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

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


    /* -- Views -- */


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

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

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

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

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

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

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

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

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

    }


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

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

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

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

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

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

	    };
	}

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

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

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

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

    }


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

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

    // find matching key
    K findKey(Object key) {
	    processQueue();
      K kkey = (K) key;
	    // TODO: use replacement for HashMap to avoid reflection
	    WeakKey wkey = WeakKeyCreate(kkey);
	    WeakKey found = hashMap_findKey(hash, wkey);
	    return found == null ? null : found.get();
    }
}static abstract class F1<A, B> {
  abstract B get(A a);
}

static <A, B> void put(Map<A, B> map, A a, B b) {
  if (map != null) map.put(a, b);
}
static <A> Iterator<A> iterator(Collection<A> c) {
  return c == null ? emptyIterator() : c.iterator();
}
static String lower(String s) {
  return s == null ? null : s.toLowerCase();
}

static char lower(char c) {
  return Character.toLowerCase(c);
}
static boolean isDollarVar(String s) {
  return startsWith(s, '$') && isJavaIdentifierAfter(s, 1);
}


static boolean isDollarVar(Symbol s) {
  return s != null && s.master.dollarVar;
}

// 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 Method hashMap_findKey_method;

static <A, B> A hashMap_findKey(HashMap<A, B> map, Object key) { try {
  if (hashMap_findKey_method == null)
    hashMap_findKey_method = findMethodNamed(HashMap.class, "getNode");
  Map.Entry<A, B> entry = (Map.Entry) hashMap_findKey_method.invoke(map, hashMap_internalHash(key), key);
  // java.util.Map.Entry<A, B> entry = (java.util.Map.Entry) call(hash, 'getNode, hashMap_internalHash(key), wkey);
  return entry == null ? null : entry.getKey();
} catch (Exception __e) { throw rethrow(__e); } }
static <A> void remove(List<A> l, int i) {
  if (l != null && i >= 0 && i < l(l))
    l.remove(i);
}

static <A> void remove(Collection<A> l, A a) {
  if (l != null) l.remove(a);
}
static char charAt(String s, int i) {
  return s != null && i >= 0 && i < s.length() ? s.charAt(i) : '\0';
}


// This is a bit rough... finds static and non-static methods.

static Method findMethodNamed(Object obj, String method) {
  if (obj == null) return null;
  if (obj instanceof Class)
    return findMethodNamed((Class) obj, method);
  return findMethodNamed(obj.getClass(), method);
}

static Method findMethodNamed(Class c, String method) {
  while (c != null) {
    for (Method m : c.getDeclaredMethods())
      if (m.getName().equals(method)) {
        m.setAccessible(true);
        return m;
      }
    c = c.getSuperclass();
  }
  return null;
}
static int hashMap_internalHash(Object key) {
  int h;
  return (key == null) ? 0 : (h = key.hashCode()) ^ (h >>> 16);
}
static 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 boolean isJavaIdentifierAfter(String s, int i) {
  int n = l(s);
  if (i >= n || !Character.isJavaIdentifierStart(s.charAt(i)))
    return false;
  for (i++; i < n; i++)
    if (!Character.isJavaIdentifierPart(s.charAt(i)))
      return false;
  return true;
}

}