import java.math.*;
import javax.imageio.*;
import java.awt.image.*;
import java.awt.event.*;
import java.awt.*;
import java.security.spec.*;
import java.security.*;
import java.lang.management.*;
import java.lang.ref.*;
import java.lang.reflect.*;
import java.net.*;
import java.io.*;
import javax.swing.table.*;
import javax.swing.text.*;
import javax.swing.event.*;
import javax.swing.*;
import java.util.concurrent.atomic.*;
import java.util.concurrent.*;
import java.util.regex.*;
import java.util.List;
import java.util.zip.*;
import java.util.*;
public class main {
// a Lisp-like form
static class Lisp implements Iterable<Lisp> {
  String head;
  List<Lisp> args = new ArrayList<Lisp>();
  
  Lisp() {}
  Lisp(String head) {
  this.head = head;}
  
  public String toString() {
    if (args.isEmpty())
      return quoteIfNotIdentifier(head);
    List<String> bla = new ArrayList<String>();
    for (Lisp a : args)
      bla.add(a.toString());
    String inner = join(", ", bla);
    if (head.equals(""))
      return "{" + inner + "}"; // list
    else
      return quoteIfNotIdentifier(head) + "(" + inner + ")";
  }
  
  void add(Lisp l) {
    args.add(l);
  }
  
  void add(String s) {
    args.add(new Lisp(s));
  }
  
  int size() {
    return args.size();
  }
  
  boolean isEmpty() {
    return args.isEmpty();
  }
  
  Lisp get(int i) {
    return args.get(i);
  }
  
  String getString(int i) {
    return get(i).head;
  }
  
  String s(int i) {
    return getString(i);
  }
  
  boolean is(String... heads) {
    return asList(heads).contains(head);
  }
  
  public Iterator<Lisp> iterator() {
    return args.iterator();
  }
  
  Lisp subList(int fromIndex, int toIndex) {
    Lisp l = new Lisp(head);
    l.args.addAll(args.subList(fromIndex, toIndex)); // better to copy here I guess - safe
    return l;
  }
}



static List<Lisp> statements = new ArrayList<Lisp>();

public static void main(String[] args) throws Exception {
  init();
  dialog();
}

static Lisp lisplist(Object... x) { return lisp("", x); }
static Lisp enter(Object... x) { return lisp("enter", x); }
static Lisp answer(Object... x) { return lisp("answer", x); }
static Lisp or(Object... x) { return lisp("or", x); }

static void init() {
  Lisp statement = lisplist(
    enter("An image has pixels."),
    enter("What does an image have?"),
    answer(or("pixels", "An image has pixels."))
  );
  statements.add(statement);
  //print(structure(statement));
  print(statement);
}

static void dialog() {
  Lisp list = lisplist();
  while (true) {
    System.out.print("LISP> ");
    String s = readLine();
    if (s == null) break;
    s = s.trim();
    if (s.equalsIgnoreCase("bye")) break;
    if (s.equals("!new")) {
      list = lisplist();
      print("! ok");
      continue;
    }
    /*if (s.startsWith("?")) {
      s = s.substring(1).trim();
      list.add(ask(s));
      print("List now: " + list);
    } else {*/
      list.add(enter(s));
      print("List now: " + list);
    //}
    
    String a = chimeIn(list);
    if (a != null) {
      list.add(answer(a));
      print("! " + a);
    }
  }
}

static class Match {
  Lisp statement;
  int i;
  
  Match(Lisp statement, int i) {
  this.i = i;
  this.statement = statement;}
}

static String chimeIn(Lisp history) {
  Match match = matchFromBeginning(history);
  print("Match: " + structure(match));
  if (match != null && match.i < match.statement.size()) {
    Lisp next = match.statement.get(match.i);
    if (next.is("answer"))
      if (next.get(0).is("or"))
        return next.get(0).getString(0);
      else
        return next.getString(0);
  }
  return null;
}

static Match matchFromBeginning(Lisp history) {
  Match best = null;
  for (Lisp statement : statements) {
    Match match = getMatch(statement, history);
    if (best == null || match.i > best.i)
      best = match;
  }
  return best;
}

static Match getMatch(Lisp statement, Lisp history) {
  int n = Math.min(statement.size(), history.size());
  int i = 0;
  while (i < n)
    if (!matchLine(statement.get(i), history.get(i)))
      break;
    else
      ++i;
  return new Match(statement, i);
}

static boolean matchLine(Lisp l1, Lisp l2) {
  if (l1.is("enter"))
    return l1.head.equals(l2.head) && sentenceEq(l1.getString(0), l2.getString(0));
  return l1.equals(l2);
}


static StringBuffer print_log;

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

static void print(Object o) {
  String s = String.valueOf(o) + "\n";
  synchronized(StringBuffer.class) {
    if (print_log == null) print_log = new StringBuffer();
  }
  print_log.append(s);
  System.out.print(s);
}

static void print(long l) {
  print(String.valueOf(l));
}

// make a lisp form
static Lisp lisp(String head, Object... args) {
  Lisp l = new Lisp(head);
  for (Object o : args)
    if (o instanceof String)
      l.args.add(new Lisp((String) o));
    else if (o instanceof Lisp)
      l.args.add((Lisp) o);
    else
      fail("Bad argument type: " + o);
  return l;
}


  static boolean sentenceEq(String a, String b) {
    List<String> tok1 = parse3(a), tok2 = parse3(b);
    if (tok1.size() != tok2.size()) return false;
    for (int i = 0; i < tok1.size(); i++)
      if (!tok1.get(i).equalsIgnoreCase(tok2.get(i)))
        return false;
    return true;
  }

static BufferedReader readLine_reader;

static String readLine() {
  return (String) call(getJavaX(), "readLine");
}

static String structure(Object o) {
  return structure(o, 0);
}

// leave to false, unless unstructure() breaks
static boolean structure_allowShortening = false;
  
static String structure(Object o, int stringSizeLimit) {
  if (o == null) return "null";
  String name = o.getClass().getName();
  
  StringBuilder buf = new StringBuilder();
  
  if (o instanceof Collection) { // TODO: store the type (e.g. HashSet/TreeSet)
    for (Object x : (Collection) o) {
      if (buf.length() != 0) buf.append(", ");
      buf.append(structure(x, stringSizeLimit));
    }
    return "[" + buf + "]";
  }
  
  if (o instanceof Map) {
    for (Object e : ((Map) o).entrySet()) {
      if (buf.length() != 0) buf.append(", ");
      buf.append(structure(((Map.Entry) e).getKey(), stringSizeLimit));
      buf.append("=");
      buf.append(structure(((Map.Entry) e).getValue(), stringSizeLimit));
    }
    return (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(Array.get(o, i), stringSizeLimit));
    }
    return "array{" + buf + "}";
  }

  if (o instanceof String)
    return quote(stringSizeLimit != 0 ? shorten((String) o, stringSizeLimit) : (String) o);
    
  if (o instanceof Class)
    return "class(" + quote(((Class) o).getName()) + ")";
    
  if (o instanceof Throwable)
    return "exception(" + quote(((Throwable) o).getMessage()) + ")";
    
  if (o instanceof BigInteger)
    return "bigint(" + o + ")";
  
  if (o instanceof Double)
    return "d(" + quote(str(o)) + ")";
    
  if (o instanceof Long)
    return o + "L";
  
  // Need more cases? This should cover all library classes...
  if (name.startsWith("java.") || name.startsWith("javax."))
    return String.valueOf(o);
    
  String shortName = o.getClass().getName().replaceAll("^main\\$", "");
  
  int numFields = 0;
  String fieldName = "";
  if (shortName.equals("DynamicObject")) {
    shortName = (String) get(o, "className");
    Map<String, Object> 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(value, stringSizeLimit));
      }
      ++numFields;
   }
  } else {
    // regular class
    // TODO: go to superclasses too
    Field[] fields = o.getClass().getDeclaredFields();
    for (Field field : fields) {
      if ((field.getModifiers() & Modifier.STATIC) != 0)
        continue;
      Object value;
      try {
        field.setAccessible(true);
        value = field.get(o);
      } catch (Exception e) {
        value = "?";
      }
      
      fieldName = field.getName();
      
      // put special cases here...
  
      if (value != null) {
        if (buf.length() != 0) buf.append(", ");
        buf.append(fieldName + "=" + structure(value, stringSizeLimit));
      }
      ++numFields;
    }
  }
  
  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 s;
}

static Class __javax;

static Class getJavaX() {
  return __javax;
}

  static List<String> parse3(String s) {
    return dropPunctuation(javaTokPlusPeriod(s));
  }

  // 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 String str(Object o) {
  return String.valueOf(o);
}

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

static <A> 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());
}

// 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<String> dropPunctuation_keep = litlist("*", "<", ">");

static List<String> dropPunctuation(List<String> tok) {
  tok = new ArrayList<String>(tok);
  for (int i = 1; i < tok.size(); i += 2) {
    String t = tok.get(i);
    if (t.length() == 1 && !Character.isLetter(t.charAt(0)) && !Character.isDigit(t.charAt(0)) && !dropPunctuation_keep.contains(t)) {
      tok.set(i-1, tok.get(i-1) + tok.get(i+1));
      tok.remove(i);
      tok.remove(i);
      i -= 2;
    }
  }
  return tok;
}

static String dropPunctuation(String s) {
  return join(dropPunctuation(nlTok(s)));
}


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

  static String format(String pat, Object... args) {
    return format3(pat, args);
  }


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();
} 



// 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<String> javaTokPlusPeriod(String s) {
  List<String> tok = new ArrayList<String>();
  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 (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 String format3(String pat, Object... args) {
    if (args.length == 0) return pat;
    
    List<String> 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 <A> ArrayList<A> litlist(A... a) {
  return new ArrayList<A>(Arrays.asList(a));
}

  public static String join(String glue, Iterable<String> strings) {
    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));
  }
  
  public static String join(Iterable<String> strings) {
    return join("", strings);
  }
  
  public static String join(String[] strings) {
    return join("", strings);
  }


static List<String> nlTok(String s) {
  return javaTokPlusPeriod(s);
}

static boolean isIdentifier(String s) {
  return isJavaIdentifier(s);
}

static boolean isNonNegativeInteger(String s) {
  return s != null && Pattern.matches("\\d+", s);
}

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;
}

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

static String quoteIfNotIdentifier(String s) {
  if (s == null) return null;
  return isJavaIdentifier(s) ? s : quote(s);
}

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

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

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

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

static String getString(Map map, Object key) {
  return map == null ? null : (String) map.get(key);
}

static String getString(List l, int idx) {
  return (String) get(l, idx);
}

static String getString(Object o, Object key) {
  if (o instanceof Map) return getString((Map) o, key);
  if (key instanceof String)
    return (String) get(o, (String) key);
  throw fail("Not a string key: " + getClassName(key));
}

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

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


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