六子棋建立博弈树α-β剪枝算法代码C语言

下面是六子棋建立博弈树α-β剪枝算法的代码，使用C语言实现： ``` #include <stdio.h> #include <stdlib.h> #include <limits.h> #define BOARD_SIZE 6 #define EMPTY 0 #define PLAYER1 1 #define PLAYER2 2 int board[BOARD_SIZE][BOARD_SIZE]; // 判断当前棋盘状态下是否有玩家获胜 int is_win(int player) { int i, j, k; // 横向检查 for (i = 0; i < BOARD_SIZE; i++) { for (j = 0; j < BOARD_SIZE - 5; j++) { for (k = 0; k < 6; k++) { if (board[i][j + k] != player) { break; } } if (k == 6) { return 1; } } } // 竖向检查 for (i = 0; i < BOARD_SIZE - 5; i++) { for (j = 0; j < BOARD_SIZE; j++) { for (k = 0; k < 6; k++) { if (board[i + k][j] != player) { break; } } if (k == 6) { return 1; } } } // 左上到右下斜线检查 for (i = 0; i < BOARD_SIZE - 5; i++) { for (j = 0; j < BOARD_SIZE - 5; j++) { for (k = 0; k < 6; k++) { if (board[i + k][j + k] != player) { break; } } if (k == 6) { return 1; } } } // 右上到左下斜线检查 for (i = 5; i < BOARD_SIZE; i++) { for (j = 0; j < BOARD_SIZE - 5; j++) { for (k = 0; k < 6; k++) { if (board[i - k][j + k] != player) { break; } } if (k == 6) { return 1; } } } return 0; } // 计算当前棋盘状态的得分 int evaluate_board() { int i, j, k, player1_score, player2_score; // 横向得分 player1_score = player2_score = 0; for (i = 0; i < BOARD_SIZE; i++) { for (j = 0; j < BOARD_SIZE - 5; j++) { int player1_count = 0, player2_count = 0; for (k = 0; k < 6; k++) { if (board[i][j + k] == PLAYER1) { player1_count++; } else if (board[i][j + k] == PLAYER2) { player2_count++; } } if (player1_count > 0 && player2_count == 0) { player1_score += 10; } else if (player2_count > 0 && player1_count == 0) { player2_score += 10; } } } // 竖向得分 for (i = 0; i < BOARD_SIZE - 5; i++) { for (j = 0; j < BOARD_SIZE; j++) { int player1_count = 0, player2_count = 0; for (k = 0; k < 6; k++) { if (board[i + k][j] == PLAYER1) { player1_count++; } else if (board[i + k][j] == PLAYER2) { player2_count++; } } if (player1_count > 0 && player2_count == 0) { player1_score += 10; } else if (player2_count > 0 && player1_count == 0) { player2_score += 10; } } } // 左上到右下斜线得分 for (i = 0; i < BOARD_SIZE - 5; i++) { for (j = 0; j < BOARD_SIZE - 5; j++) { int player1_count = 0, player2_count = 0; for (k = 0; k < 6; k++) { if (board[i + k][j + k] == PLAYER1) { player1_count++; } else if (board[i + k][j + k] == PLAYER2) { player2_count++; } } if (player1_count > 0 && player2_count == 0) { player1_score += 10; } else if (player2_count > 0 && player1_count == 0) { player2_score += 10; } } } // 右上到左下斜线得分 for (i = 5; i < BOARD_SIZE; i++) { for (j = 0; j < BOARD_SIZE - 5; j++) { int player1_count = 0, player2_count = 0; for (k = 0; k < 6; k++) { if (board[i - k][j + k] == PLAYER1) { player1_count++; } else if (board[i - k][j + k] == PLAYER2) { player2_count++; } } if (player1_count > 0 && player2_count == 0) { player1_score += 10; } else if (player2_count > 0 && player1_count == 0) { player2_score += 10; } } } return player1_score - player2_score; } // 枚举所有空位，计算当前玩家的得分 int alpha_beta_search(int alpha, int beta, int depth, int player) { int i, j, value, best_value; if (is_win(PLAYER1)) { return INT_MAX; } else if (is_win(PLAYER2)) { return INT_MIN; } else if (depth == 0) { return evaluate_board(); } if (player == PLAYER1) { best_value = INT_MIN; for (i = 0; i < BOARD_SIZE; i++) { for (j = 0; j < BOARD_SIZE; j++) { if (board[i][j] == EMPTY) { board[i][j] = PLAYER1; value = alpha_beta_search(alpha, beta, depth - 1, PLAYER2); board[i][j] = EMPTY; if (value > best_value) { best_value = value; } if (best_value > alpha) { alpha = best_value; } if (alpha >= beta) { return best_value; } } } } } else { best_value = INT_MAX; for (i = 0; i < BOARD_SIZE; i++) { for (j = 0; j < BOARD_SIZE; j++) { if (board[i][j] == EMPTY) { board[i][j] = PLAYER2; value = alpha_beta_search(alpha, beta, depth - 1, PLAYER1); board[i][j] = EMPTY; if (value < best_value) { best_value = value; } if (best_value < beta) { beta = best_value; } if (alpha >= beta) { return best_value; } } } } } return best_value; } // 根据当前玩家的得分，找到最佳落子位置 void find_best_move(int *x, int *y) { int i, j, value, best_value; *x = *y = -1; best_value = INT_MIN; for (i = 0; i < BOARD_SIZE; i++) { for (j = 0; j < BOARD_SIZE; j++) { if (board[i][j] == EMPTY) { board[i][j] = PLAYER1; value = alpha_beta_search(INT_MIN, INT_MAX, 5, PLAYER2); board[i][j] = EMPTY; if (value > best_value) { best_value = value; *x = i; *y = j; } } } } } int main() { int i, j, x, y; // 初始化棋盘 for (i = 0; i < BOARD_SIZE; i++) { for (j = 0; j < BOARD_SIZE; j++) { board[i][j] = EMPTY; } } // 玩家和AI轮流下棋，直到有一方获胜或棋盘已满 while (!is_win(PLAYER1) && !is_win(PLAYER2)) { // 玩家下棋 printf("Enter your move (row column): "); scanf("%d %d", &x, &y); if (board[x][y] != EMPTY) { printf("Invalid move!\n"); continue; } board[x][y] = PLAYER2; // AI下棋 find_best_move(&x, &y); board[x][y] = PLAYER1; // 输出当前棋盘状态 for (i = 0; i < BOARD_SIZE; i++) { for (j = 0; j < BOARD_SIZE; j++) { printf("%d ", board[i][j]); } printf("\n"); } printf("\n"); } // 输出获胜者 if (is_win(PLAYER1)) { printf("AI wins!\n"); } else if (is_win(PLAYER2)) { printf("You win!\n"); } else { printf("Draw!\n"); } return 0; } ``` 注意，这只是一个简单的示例代码，可能存在一些问题和需要完善的地方。如果你想使用这个代码进行实际的游戏，需要进一步优化和改进。