Changed the king heuristic so that kings are worth twice as much as n…

…ormal pieces. For some reason Collections.max blows up on containers of type Double.

src/controller/Game.java

@@ -106,7 +106,7 @@ public class Game {
 	public Move getMinimaxMove(int depth, boolean inJumpSequence) {
 		ArrayList<Board> boardFrontier = null;
 		ArrayList<Move> moveFrontier = null;
-		ArrayList<Double> moveScores = new ArrayList<Double>();
+		ArrayList<Integer> moveScores = new ArrayList<Integer>();
 
 		if (inJumpSequence) {
 			/* Generate the frontier only for the piece that just moves */
@@ -140,7 +140,7 @@ public class Game {
 		}
 
 		/* Determine the maximum minimax score and which move led to that score */
-		double maxScore = Double.MIN_VALUE;
+		int maxScore = Integer.MIN_VALUE;
 		Move bestMove = null;
 
 		for (int i = 0; i < moveScores.size(); ++i) {
@@ -159,9 +159,9 @@ public class Game {
 		return bestMove;
 	}
 
-	public double getMinimaxScore(Color color, Board b, int depth, boolean inJumpSequence) {
+	public int getMinimaxScore(Color color, Board b, int depth, boolean inJumpSequence) {
 		ArrayList<Board> boardFrontier;
-		ArrayList<Double> moveScores = new ArrayList<Double>();
+		ArrayList<Integer> moveScores = new ArrayList<Integer>();
 		Color otherColor = (color == Color.BLACK ? Color.WHITE : Color.BLACK);
 
 		if (depth == 0) {
@@ -196,7 +196,7 @@ public class Game {
 		}
 
 		for (Board board : boardFrontier) {
-			double moveScore = getMinimaxScore(nextColor, board, depth - 1, inJumpSequence);
+			int moveScore = getMinimaxScore(nextColor, board, depth - 1, inJumpSequence);
 			moveScores.add(moveScore);
 		}
 

src/model/Board.java

@@ -387,10 +387,10 @@ public class Board {
 				location.row == BOARD_SIZE - 1 );
 	}
 
-	public double getHeuristic(Color color) {
+	public int getHeuristic(Color color) {
 		/* Kings are weighted more, so we count for them twice */
-		double blackHeuristic = blackPieces + blackKings * 1.5;
-		double whiteHeuristic = whitePieces + whiteKings * 1.5;
+		int blackHeuristic = blackPieces + blackKings * 2;
+		int whiteHeuristic = whitePieces + whiteKings * 2;
 		return - (color == Color.BLACK ? 
 				(blackHeuristic - whiteHeuristic) : 
 					(whiteHeuristic - blackHeuristic));