heuristic + arena + alphabeta

javaAPI/fr/iut_fbleau/HexGame/MiniMaxBot.java

@@ -0,0 +1,89 @@
+package fr.iut_fbleau.HexGame;
+
+import fr.iut_fbleau.GameAPI.*;
+
+public class MiniMaxBot extends AbstractGamePlayer {
+
+    private int MAXDEPTH = 5;
+
+    public MiniMaxBot(Player me) {
+        super(me);  // Correct constructor usage
+    }
+
+    @Override
+    public AbstractPly giveYourMove(IBoard board) {
+        HexBoard hb = (HexBoard) board;
+        float bestScore = -Float.MAX_VALUE;
+        HexPly bestMove = null;
+
+        for (int i = 0; i < hb.getSize(); i++) {
+            for (int j = 0; j < hb.getSize(); j++) {
+                HexPly move = new HexPly(hb.getCurrentPlayer(), i, j);
+                if (hb.isLegal(move)) {
+                    hb.doPly(move);
+                    float score = minimax(hb, MAXDEPTH, -Float.MAX_VALUE, Float.MAX_VALUE, true);
+                    if (score > bestScore) {
+                        bestScore = score;
+                        bestMove = move;
+                    }
+                    hb.undoPly();
+                }
+            }
+        }
+        return bestMove;
+    }
+
+    private float minimax(HexBoard board, int depth, float alpha, float beta, boolean isMaximizing) {
+        if (depth == 0 || board.isGameOver()) {
+            return evaluateBoard(board);
+        }
+
+        if (isMaximizing) {
+            float bestScore = -Float.MAX_VALUE;
+            for (int i = 0; i < board.getSize(); i++) {
+                for (int j = 0; j < board.getSize(); j++) {
+                    HexPly move = new HexPly(board.getCurrentPlayer(), i, j);
+                    if (board.isLegal(move)) {
+                        board.doPly(move);
+                        float score = minimax(board, depth - 1, alpha, beta, false);
+                        bestScore = Math.max(bestScore, score);
+                        alpha = Math.max(alpha, bestScore);
+                        if (beta <= alpha) break; // Pruning
+                        board.undoPly();
+                    }
+                }
+            }
+            return bestScore;
+        } else {
+            float bestScore = Float.MAX_VALUE;
+            for (int i = 0; i < board.getSize(); i++) {
+                for (int j = 0; j < board.getSize(); j++) {
+                    HexPly move = new HexPly(board.getCurrentPlayer(), i, j);
+                    if (board.isLegal(move)) {
+                        board.doPly(move);
+                        float score = minimax(board, depth - 1, alpha, beta, true);
+                        bestScore = Math.min(bestScore, score);
+                        beta = Math.min(beta, bestScore);
+                        if (beta <= alpha) break; // Pruning
+                        board.undoPly();
+                    }
+                }
+            }
+            return bestScore;
+        }
+    }
+
+    private float evaluateBoard(HexBoard board) {
+        int size = board.getSize();
+        int center = size / 2;
+        int score = 0;
+        for (int i = 0; i < size; i++) {
+            for (int j = 0; j < size; j++) {
+                if (board.getPlayerAt(i, j) == Player.PLAYER1) {
+                    score += Math.abs(i - center) + Math.abs(j - center); // Distance from center
+                }
+            }
+        }
+        return score;
+    }
+}