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 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.*; public class main { static class Puzzler { List remainingTokens = new ArrayList(); List numbers = new ArrayList(); List vars = new ArrayList(); boolean aggressiveFirst = true; boolean useAllTokens = true; int maxTries = 1000; boolean initVars = true; String code = ""; Puzzler(String tokens) { for (String s : codeTokens(javaTok(tokens))) if (eq(s, "i") || eq(s, "j")) { vars.add(s); if (initVars) code += s + " = 0\n"; } else if (isInteger(s)) numbers.add(s); else remainingTokens.add(s); } String var() { return oneOf(vars); } String exp() { /*int i = random(2); S s = "?"; switch (i) { case 0: s = "0"; case 1: s = "9"; }*/ String s = oneOf(concatLists(numbers, vars)); if (random(3) == 0) s = "get(" + s + ")"; return s; } String swap() { return "swap(" + exp() + ", " + exp() + ")\n"; } String _for() { return "for " + var() + " = " + exp() + ", " + exp() + "-1 do\n" + indentx(code()) + "end\n"; } String ifless() { return "if " + exp() + " < " + exp() + " then\n" + indentx(code()) + "end\n"; } String code() { String s = choose("swap", "for", "ifless"); if (s == null) return ""; return (String) call(this, eq(s, "for") ? "_for" : s); /*if (eq(s, "swap")) ret swap(); if (eq(s, "for")) ret for();*/ } String main() { if (useAllTokens) return code + code(); List tokens = cloneList(remainingTokens); for (int i = 0; i < maxTries; i++) { remainingTokens = cloneList(tokens); String s = code(); if (empty(remainingTokens)) return code + s; } throw fail("Can't solve using all tokens: " + structure(tokens)); } String choose(String... options) { List l = new ArrayList(); if (aggressiveFirst && nempty(remainingTokens) && contains(options, first(remainingTokens))) { String s = first(remainingTokens); remainingTokens.remove(0); return s; } for (String s : options) if (remainingTokens.contains(s)) l.add(s); String choice = oneOf(l); if (choice != null) remainingTokens.remove(choice); return choice; } } /* for(variable, exp, exp, code) -> code ifless(exp, exp, code) -> code swap(exp, exp) -> code variable -> exp number -> exp get(exp) -> exp // << always available, at least one level deep */ // Puzzler for Bubblesort static String makeLua() { Puzzler p = new Puzzler("0 10 i j for for ifless swap"); p.aggressiveFirst = true; return p.main(); } static List codeTokens(List tok) { return codeTokensOnly(tok); } // replacement for class JavaTok // maybe incomplete, might want to add floating point numbers // todo also: extended multi-line strings static List javaTok(String s) { List tok = new ArrayList(); int l = s.length(); int i = 0; while (i < l) { int j = i; char c; String cc; // scan for whitespace while (j < l) { c = s.charAt(j); cc = s.substring(j, Math.min(j+2, l)); if (c == ' ' || c == '\t' || c == '\r' || c == '\n') ++j; else if (cc.equals("/*")) { do ++j; while (j < l && !s.substring(j, Math.min(j+2, l)).equals("*/")); j = Math.min(j+2, l); } else if (cc.equals("//")) { do ++j; while (j < l && "\r\n".indexOf(s.charAt(j)) < 0); } else break; } tok.add(s.substring(i, j)); i = j; if (i >= l) break; c = s.charAt(i); // cc is not needed in rest of loop body cc = s.substring(i, Math.min(i+2, l)); // 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 (cc.equals("[[")) { do ++j; while (j+1 < l && !s.substring(j, j+2).equals("]]")); j = Math.min(j+2, l); } else if (cc.equals("[=") && 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(s.substring(i, j)); i = j; } if ((tok.size() % 2) == 0) tok.add(""); return tok; } static List javaTok(List tok) { return javaTok(join(tok)); } static boolean nempty(Collection c) { return !isEmpty(c); } static boolean nempty(String s) { return !isEmpty(s); } static List cloneList(Collection l) { //O mutex = getOpt(l, "mutex"); /*if (mutex != null) synchronized(mutex) { ret new ArrayList(l); } else ret new ArrayList(l);*/ // assume mutex is equal to collection, which will be true unless you explicitly pass a mutex to synchronizedList() which no one ever does. synchronized(l) { return new ArrayList(l); } } static boolean eq(Object a, Object b) { if (a == null) return b == null; if (a.equals(b)) return true; if (a instanceof BigInteger) { if (b instanceof Integer) return a.equals(BigInteger.valueOf((Integer) b)); if (b instanceof Long) return a.equals(BigInteger.valueOf((Long) b)); } return false; } static String structure(Object o) { HashSet refd = new HashSet(); return structure_2(structure_1(o, 0, new IdentityHashMap(), refd), refd); } // leave to false, unless unstructure() breaks static boolean structure_allowShortening = false; static String structure_1(Object o, int stringSizeLimit, IdentityHashMap seen, HashSet refd) { if (o == null) return "null"; // these are never back-referenced (for readability) if (o instanceof String) return quote(stringSizeLimit != 0 ? shorten((String) o, stringSizeLimit) : (String) o); if (o instanceof BigInteger) return "bigint(" + o + ")"; if (o instanceof Double) return "d(" + quote(str(o)) + ")"; if (o instanceof Long) return o + "L"; if (o instanceof Integer) return str(o); if (o instanceof Boolean) return ((Boolean) o).booleanValue() ? "t" : "f"; Integer ref = seen.get(o); if (ref != null) { refd.add(ref); return "r" + ref; } ref = seen.size()+1; seen.put(o, ref); String r = "m" + ref + " "; // marker String name = o.getClass().getName(); StringBuilder buf = new StringBuilder(); if (o instanceof HashSet) return r + "hashset " + structure_1(new ArrayList((Set) o), stringSizeLimit, seen, refd); if (o instanceof TreeSet) return r + "treeset " + structure_1(new ArrayList((Set) o), stringSizeLimit, seen, refd); if (o instanceof Collection) { for (Object x : (Collection) o) { if (buf.length() != 0) buf.append(", "); buf.append(structure_1(x, stringSizeLimit, seen, refd)); } return r + "[" + buf + "]"; } if (o instanceof Map) { for (Object e : ((Map) o).entrySet()) { if (buf.length() != 0) buf.append(", "); buf.append(structure_1(((Map.Entry) e).getKey(), stringSizeLimit, seen, refd)); buf.append("="); buf.append(structure_1(((Map.Entry) e).getValue(), stringSizeLimit, seen, refd)); } return r + (o instanceof HashMap ? "hashmap" : "") + "{" + buf + "}"; } if (o.getClass().isArray()) { int n = Array.getLength(o); for (int i = 0; i < n; i++) { if (buf.length() != 0) buf.append(", "); buf.append(structure_1(Array.get(o, i), stringSizeLimit, seen, refd)); } return r + "array{" + buf + "}"; } if (o instanceof Class) return r + "class(" + quote(((Class) o).getName()) + ")"; if (o instanceof Throwable) return r + "exception(" + quote(((Throwable) o).getMessage()) + ")"; if (o instanceof BitSet) { BitSet bs = (BitSet) o; for (int i = bs.nextSetBit(0); i >= 0; i = bs.nextSetBit(i+1)) { if (buf.length() != 0) buf.append(", "); buf.append(i); } return "bitset{" + buf + "}"; } // Need more cases? This should cover all library classes... if (name.startsWith("java.") || name.startsWith("javax.")) return r + String.valueOf(o); String shortName = o.getClass().getName().replaceAll("^main\\$", ""); if (shortName.equals("Lisp")) { buf.append("l(" + structure_1(getOpt(o, "head"), stringSizeLimit, seen, refd)); List args = (List) ( getOpt(o, "args")); if (nempty(args)) for (int i = 0; i < l(args); i++) { buf.append(", "); Object arg = args.get(i); // sweet shortening if (arg != null && eq(arg.getClass().getName(), "main$Lisp") && isTrue(call(arg, "isEmpty"))) arg = get(arg, "head"); buf.append(structure_1(arg, stringSizeLimit, seen, refd)); } buf.append(")"); return r + str(buf); } int numFields = 0; String fieldName = ""; if (shortName.equals("DynamicObject")) { shortName = (String) get(o, "className"); Map fieldValues = (Map) get(o, "fieldValues"); for (String _fieldName : fieldValues.keySet()) { fieldName = _fieldName; Object value = fieldValues.get(fieldName); if (value != null) { if (buf.length() != 0) buf.append(", "); buf.append(fieldName + "=" + structure_1(value, stringSizeLimit, seen, refd)); } ++numFields; } } else { // regular class Class c = o.getClass(); while (c != Object.class) { Field[] fields = c.getDeclaredFields(); for (Field field : fields) { if ((field.getModifiers() & Modifier.STATIC) != 0) continue; fieldName = field.getName(); // skip outer object reference if (fieldName.indexOf("$") >= 0) continue; Object value; try { field.setAccessible(true); value = field.get(o); } catch (Exception e) { value = "?"; } // put special cases here... if (value != null) { if (buf.length() != 0) buf.append(", "); buf.append(fieldName + "=" + structure_1(value, stringSizeLimit, seen, refd)); } ++numFields; } c = c.getSuperclass(); } } String b = buf.toString(); if (numFields == 1 && structure_allowShortening) b = b.replaceAll("^" + fieldName + "=", ""); // drop field name if only one String s = shortName; if (buf.length() != 0) s += "(" + b + ")"; return r + s; } // drop unused markers static String structure_2(String s, HashSet refd) { List tok = javaTok(s); StringBuilder out = new StringBuilder(); for (int i = 1; i < l(tok); i += 2) { String t = tok.get(i); if (t.startsWith("m") && isInteger(t.substring(1)) && !refd.contains(parseInt(t.substring(1)))) continue; out.append(t).append(tok.get(i+1)); } return str(out); } static boolean empty(Collection c) { return isEmpty(c); } static boolean empty(String s) { return isEmpty(s); } static boolean empty(Map map) { return map == null || map.isEmpty(); } // 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() & 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 int random(int n) { return new Random().nextInt(n); } static RuntimeException fail() { throw new RuntimeException("fail"); } static RuntimeException fail(Object msg) { throw new RuntimeException(String.valueOf(msg)); } static RuntimeException fail(String msg) { throw new RuntimeException(unnull(msg)); } static RuntimeException fail(String msg, Object... args) { throw new RuntimeException(format(msg, args)); } static boolean isInteger(String s) { return s != null && Pattern.matches("\\-?\\d+", s); } static A oneOf(List l) { return l.isEmpty() ? null : l.get(new Random().nextInt(l.size())); } static boolean contains(Collection c, Object o) { return c != null && c.contains(o); } static boolean contains(Object[] x, Object o) { if (x != null) for (Object a : x) if (eq(a, o)) return true; return false; } static List concatLists(List... lists) { List l = new ArrayList(); for (List list : lists) if (list != null) l.addAll(list); return l; } static List concatLists(Collection> lists) { List l = new ArrayList(); for (List list : lists) if (list != null) l.addAll(list); return l; } static String indentx(String s) { return dropSuffix(repeat(' ', indent_default), indent(indent_default, s)); } static Object first(Object list) { return ((List) list).isEmpty() ? null : ((List) list).get(0); } static A first(List list) { return list.isEmpty() ? null : list.get(0); } static A first(A[] bla) { return bla == null || bla.length == 0 ? null : bla[0]; } static int indent_default = 2; static String indent(int indent) { return repeat(' ', indent); } static String indent(int indent, String s) { return indent(repeat(' ', indent), s); } static String indent(String indent, String s) { return indent + s.replace("\n", "\n" + indent); } static String indent(String s) { return indent(indent_default, s); } static List indent(String indent, List lines) { List l = new ArrayList(); for (String s : lines) l.add(indent + s); return l; } static String unnull(String s) { return s == null ? "" : s; } static List unnull(List l) { return l == null ? emptyList() : l; } static String quote(String s) { if (s == null) return "null"; return "\"" + s.replace("\\", "\\\\").replace("\"", "\\\"").replace("\r", "\\r").replace("\n", "\\n") + "\""; } static String quote(long l) { return quote("" + l); } static String quote(char c) { return quote("" + c); } static String shorten(String s, int max) { if (s == null) return ""; return s.length() <= max ? s : s.substring(0, Math.min(s.length(), max)) + "..."; } // get purpose 1: access a list/array (safer version of x.get(y)) static A get(List l, int idx) { return idx >= 0 && idx < l(l) ? l.get(idx) : null; } static A get(A[] l, int idx) { return idx >= 0 && idx < l(l) ? l[idx] : null; } // get purpose 2: access a field by reflection or a map static Object get(Object o, String field) { if (o instanceof Class) return get((Class) o, field); if (o instanceof Map) return ((Map) o).get(field); if (o.getClass().getName().equals("main$DynamicObject")) return call(get_raw(o, "fieldValues"), "get", field); return get_raw(o, field); } 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() & 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 String repeat(char c, int n) { n = max(n, 0); char[] chars = new char[n]; for (int i = 0; i < n; i++) chars[i] = c; return new String(chars); } static List repeat(A a, int n) { List l = new ArrayList(); for (int i = 0; i < n; i++) l.add(a); return l; } public static String join(String glue, Iterable strings) { StringBuilder buf = new StringBuilder(); Iterator i = strings.iterator(); if (i.hasNext()) { buf.append(i.next()); while (i.hasNext()) buf.append(glue).append(i.next()); } return buf.toString(); } public static String join(String glue, String[] strings) { return join(glue, Arrays.asList(strings)); } public static String join(Iterable strings) { return join("", strings); } public static String join(String[] strings) { return join("", strings); } // 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 List codeTokensOnly(List tok) { List l = new ArrayList(); for (int i = 1; i < tok.size(); i += 2) l.add(tok.get(i)); return l; } static boolean isEmpty(Collection c) { return c == null || c.isEmpty(); } static boolean isEmpty(String s) { return s == null || s.length() == 0; } static String format(String pat, Object... args) { return format3(pat, args); } static String dropSuffix(String suffix, String s) { return s.endsWith(suffix) ? s.substring(0, l(s)-l(suffix)) : s; } static int l(Object[] array) { return array == null ? 0 : array.length; } static int l(byte[] array) { return array == null ? 0 : array.length; } static int l(int[] array) { return array == null ? 0 : array.length; } static int l(char[] array) { return array == null ? 0 : array.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(String s) { return s == null ? 0 : s.length(); } static String str(Object o) { return String.valueOf(o); } static int parseInt(String s) { return empty(s) ? 0 : Integer.parseInt(s); } static boolean isTrue(Object o) { return booleanValue(o); } static Object getOpt(Object o, String field) { if (o instanceof String) o = getBot ((String) o); if (o == null) return null; if (o instanceof Class) return getOpt((Class) o, field); if (o.getClass().getName().equals("main$DynamicObject")) return call(getOpt_raw(o, "fieldValues"), "get", field); if (o instanceof Map) return ((Map) o).get(field); return getOpt_raw(o, field); } static Object getOpt_raw(Object o, String field) { try { Field f = getOpt_findField(o.getClass(), field); if (f == null) return null; f.setAccessible(true); return f.get(o); } catch (Exception e) { throw new RuntimeException(e); } } static Object getOpt(Class c, String field) { try { Field f = getOpt_findStaticField(c, field); if (f == null) return null; f.setAccessible(true); return f.get(null); } catch (Exception e) { throw new RuntimeException(e); } } static Field getOpt_findStaticField(Class c, String field) { Class _c = c; do { for (Field f : _c.getDeclaredFields()) if (f.getName().equals(field) && (f.getModifiers() & Modifier.STATIC) != 0) return f; _c = _c.getSuperclass(); } while (_c != null); return null; } 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 String format3(String pat, Object... args) { if (args.length == 0) return pat; List tok = javaTokPlusPeriod(pat); int argidx = 0; for (int i = 1; i < tok.size(); i += 2) if (tok.get(i).equals("*")) tok.set(i, format3_formatArg(argidx < args.length ? args[argidx++] : "null")); return join(tok); } static String format3_formatArg(Object arg) { if (arg == null) return "null"; if (arg instanceof String) { String s = (String) arg; return isIdentifier(s) || isNonNegativeInteger(s) ? s : quote(s); } if (arg instanceof Integer || arg instanceof Long) return String.valueOf(arg); return quote(structure(arg)); } static List emptyList() { return Collections.emptyList(); } static Object getBot(String botID) { return call(getMainBot(), "getBot", botID); } static int max(int a, int b) { return Math.max(a, b); } 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 int max(Collection 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 boolean booleanValue(Object o) { return eq(true, o); } static boolean isIdentifier(String s) { return isJavaIdentifier(s); } static Object mainBot; static Object getMainBot() { return mainBot; } static boolean isNonNegativeInteger(String s) { return s != null && Pattern.matches("\\d+", s); } // This is made for NL parsing. // It's javaTok extended with "..." token, "$n" and "#n" and // special quotes (which are converted to normal ones). static List javaTokPlusPeriod(String s) { List tok = new ArrayList(); int l = s.length(); int i = 0; while (i < l) { int j = i; char c; String cc; // scan for whitespace while (j < l) { c = s.charAt(j); cc = s.substring(j, Math.min(j+2, l)); if (c == ' ' || c == '\t' || c == '\r' || c == '\n') ++j; else if (cc.equals("/*")) { do ++j; while (j < l && !s.substring(j, Math.min(j+2, l)).equals("*/")); j = Math.min(j+2, l); } else if (cc.equals("//")) { do ++j; while (j < l && "\r\n".indexOf(s.charAt(j)) < 0); } else break; } tok.add(s.substring(i, j)); i = j; if (i >= l) break; c = s.charAt(i); cc = s.substring(i, Math.min(i+2, l)); // scan for non-whitespace if (c == '\u201C' || c == '\u201D') c = '"'; // normalize quotes if (c == '\'' || c == '"') { char opener = c; ++j; while (j < l) { char _c = s.charAt(j); if (_c == '\u201C' || _c == '\u201D') _c = '"'; // normalize quotes if (_c == opener) { ++j; break; } else if (s.charAt(j) == '\\' && j+1 < l) j += 2; else ++j; } if (j-1 >= i+1) { tok.add(opener + s.substring(i+1, j-1) + opener); i = j; continue; } } else if (Character.isJavaIdentifierStart(c)) do ++j; while (j < l && (Character.isJavaIdentifierPart(s.charAt(j)) || s.charAt(j) == '\'')); // for things like "this one's" else if (Character.isDigit(c)) do ++j; while (j < l && Character.isDigit(s.charAt(j))); else if (cc.equals("[[")) { do ++j; while (j+1 < l && !s.substring(j, j+2).equals("]]")); j = Math.min(j+2, l); } else if (cc.equals("[=") && i+2 < l && s.charAt(i+2) == '[') { do ++j; while (j+2 < l && !s.substring(j, j+3).equals("]=]")); j = Math.min(j+3, l); } else if (s.substring(j, Math.min(j+3, l)).equals("...")) j += 3; else if (c == '$' || c == '#') do ++j; while (j < l && Character.isDigit(s.charAt(j))); else ++j; tok.add(s.substring(i, j)); i = j; } if ((tok.size() % 2) == 0) tok.add(""); return tok; } static boolean isJavaIdentifier(String s) { if (s.length() == 0 || !Character.isJavaIdentifierStart(s.charAt(0))) return false; for (int i = 1; i < s.length(); i++) if (!Character.isJavaIdentifierPart(s.charAt(i))) return false; return true; } }