Beispiel #1
0
 public int min(final Board board, final int depth) {
   if (depth == 0 || isEndGameScenario(board)) {
     return this.evaluator.evaluate(board, depth);
   }
   int lowestSeenValue = Integer.MAX_VALUE;
   for (final Move move : board.currentPlayer().getLegalMoves()) {
     final MoveTransition moveTransition = board.currentPlayer().makeMove(move);
     if (moveTransition.getMoveStatus().isDone()) {
       final int currentValue = max(moveTransition.getTransitionBoard(), depth - 1);
       if (currentValue <= lowestSeenValue) {
         lowestSeenValue = currentValue;
       }
     }
   }
   return lowestSeenValue;
 }
Beispiel #2
0
 private List<Move> orderImpl(final Board board, final int depth) {
   final List<MoveOrderEntry> moveOrderEntries = new ArrayList<>();
   final boolean SORT_DESCENDING = board.currentPlayer().getColor().isWhite();
   for (final Move move : board.currentPlayer().getLegalMoves()) {
     final MoveTransition moveTransition = board.currentPlayer().makeMove(move);
     if (moveTransition.getMoveStatus().isDone()) {
       final int currentValue =
           board.currentPlayer().getColor().isWhite()
               ? min(moveTransition.getTransitionBoard(), depth - 1)
               : max(moveTransition.getTransitionBoard(), depth - 1);
       moveOrderEntries.add(new MoveOrderEntry(move, currentValue));
     }
   }
   if (SORT_DESCENDING) {
     Collections.sort(
         moveOrderEntries,
         new Comparator<MoveOrderEntry>() {
           @Override
           public int compare(final MoveOrderEntry o1, final MoveOrderEntry o2) {
             return Ints.compare(o2.getScore(), o1.getScore());
           }
         });
   } else {
     Collections.sort(
         moveOrderEntries,
         new Comparator<MoveOrderEntry>() {
           @Override
           public int compare(final MoveOrderEntry o1, MoveOrderEntry o2) {
             return Ints.compare(o1.getScore(), o2.getScore());
           }
         });
   }
   final List<Move> orderedMoves = new ArrayList<>();
   for (final MoveOrderEntry entry : moveOrderEntries) {
     orderedMoves.add(entry.getMove());
   }
   return ImmutableList.copyOf(orderedMoves);
 }
Beispiel #3
0
 private static boolean isEndGameScenario(final Board board) {
   return board.currentPlayer().isInCheckMate()
       || board.currentPlayer().isInStaleMate()
       || board.currentPlayer().getOpponent().isInCheckMate()
       || board.currentPlayer().getOpponent().isInStaleMate();
 }