写出C语言五子棋的算法代码

以下是一个简单的五子棋AI算法的C语言代码示例，采用的是极大极小搜索算法：

#include <stdio.h>
#include <stdlib.h>

#define ROWS 15  // 棋盘行数
#define COLS 15  // 棋盘列数
#define BLACK 1  // 黑子
#define WHITE 2  // 白子
#define EMPTY 0  // 空格

int board[ROWS][COLS];  // 棋盘数组
int player;  // 玩家（黑子或白子）
int ai;  // AI（黑子或白子）

// 初始化棋盘
void init_board() {
    int i, j;
    for (i = 0; i < ROWS; i++) {
        for (j = 0; j < COLS; j++) {
            board[i][j] = EMPTY;
        }
    }
}

// 打印棋盘
void print_board() {
    int i, j;
    printf("  ");
    for (i = 0; i < COLS; i++) {
        printf("%d ", i);
    }
    printf("\n");
    for (i = 0; i < ROWS; i++) {
        printf("%d ", i);
        for (j = 0; j < COLS; j++) {
            if (board[i][j] == EMPTY) {
                printf("+ ");
            } else if (board[i][j] == BLACK) {
                printf("@ ");
            } else {
                printf("O ");
            }
        }
        printf("\n");
    }
}

// 判断是否赢了
int win(int x, int y, int player) {
    int i, j;
    int count;

    // 判断横向是否连成五子
    count = 0;
    for (j = y - 4; j <= y; j++) {
        if (j < 0 || j > COLS - 5) {
            continue;
        }
        if (board[x][j] == player &&
            board[x][j+1] == player &&
            board[x][j+2] == player &&
            board[x][j+3] == player &&
            board[x][j+4] == player) {
            return 1;
        }
    }

    // 判断纵向是否连成五子
    count = 0;
    for (i = x - 4; i <= x; i++) {
        if (i < 0 || i > ROWS - 5) {
            continue;
        }
        if (board[i][y] == player &&
            board[i+1][y] == player &&
            board[i+2][y] == player &&
            board[i+3][y] == player &&
            board[i+4][y] == player) {
            return 1;
        }
    }

    // 判断右上方是否连成五子
    count = 0;
    for (i = x + 4, j = y - 4; i >= 0 && i <= ROWS - 5 && j >= 0 && j <= COLS - 5; i--, j++) {
        if (board[i][j] == player &&
            board[i-1][j+1] == player &&
            board[i-2][j+2] == player &&
            board[i-3][j+3] == player &&
            board[i-4][j+4] == player) {
            return 1;
        }
    }

    // 判断右下方是否连成五子
    count = 0;
    for (i = x - 4, j = y - 4; i <= x && i >= 0 && j <= y && j >= 0; i++, j++) {
        if (board[i][j] == player &&
            board[i+1][j+1] == player &&
            board[i+2][j+2] == player &&
            board[i+3][j+3] == player &&
            board[i+4][j+4] == player) {
            return 1;
        }
    }

    return 0;
}

// 估值函数
int score(int x, int y, int player) {
    int i, j;
    int count;
    int score = 0;

    // 判断横向是否连成五子
    count = 0;
    for (j = y - 4; j <= y; j++) {
        if (j < 0 || j > COLS - 5) {
            continue;
        }
        for (i = x; i <= x + 4; i++) {
            if (board[i][j] == player) {
                count++;
            }
        }
        if (count == 5) {
            score += 100;
        } else if (count == 4) {
            score += 10;
        }
        count = 0;
    }

    // 判断纵向是否连成五子
    count = 0;
    for (i = x - 4; i <= x; i++) {
        if (i < 0 || i > ROWS - 5) {
            continue;
        }
        for (j = y; j <= y + 4; j++) {
            if (board[i][j] == player) {
                count++;
            }
        }
        if (count == 5) {
            score += 100;
        } else if (count == 4) {
            score += 10;
        }
        count = 0;
    }

    // 判断右上方是否连成五子
    count = 0;
    for (i = x + 4, j = y - 4; i >= 0 && i <= ROWS - 5 && j >= 0 && j <= COLS - 5; i--, j++) {
        for (int k = 0; k < 5; k++) {
            if (board[i-k][j+k] == player) {
                count++;
            }
        }
        if (count == 5) {
            score += 100;
        } else if (count == 4) {
            score += 10;
        }
        count = 0;
    }

    // 判断右下方是否连成五子
    count = 0;
    for (i = x - 4, j = y - 4; i <= x && i >= 0 && j <= y && j >= 0; i++, j++) {
        for (int k = 0; k < 5; k++) {
            if (board[i+k][j+k] == player) {
                count++;
            }
        }
        if (count == 5) {
            score += 100;
        } else if (count == 4) {
            score += 10;
        }
        count = 0;
    }

    return score;
}

// 极大极小搜索算法
int min_max_search(int depth, int alpha, int beta) {
    int i, j;
    int best_score = -99999;
    int score;
    int x, y;

    if (depth == 0) {
        return score;
    }

    // 极大层
    if (player == ai) {
        for (i = 0; i < ROWS; i++) {
            for (j = 0; j < COLS; j++) {
                if (board[i][j] == EMPTY) {
                    board[i][j] = ai;
                    score = score(i, j, ai);
                    if (win(i, j, ai)) {
                        board[i][j] = EMPTY;
                        return 99999;
                    } else {
                        score += min_max_search(depth - 1, alpha, beta);
                        if (score > best_score) {
                            best_score = score;
                            x = i;
                            y = j;
                        }
                        board[i][j] = EMPTY;
                        if (best_score > alpha) {
                            alpha = best_score;
                        }
                        if (alpha >= beta) {
                            return best_score;
                        }
                    }
                }
            }
        }
        return best_score;

    // 极小层
    } else {
        for (i = 0; i < ROWS; i++) {
            for (j = 0; j < COLS; j++) {
                if (board[i][j] == EMPTY) {
                    board[i][j] = player;
                    score = score(i, j, player);
                    if (win(i, j, player)) {
                        board[i][j] = EMPTY;
                        return -99999;
                    } else {
                        score -= min_max_search(depth - 1, alpha, beta);
                        if (score < best_score) {
                            best_score = score;
                            x = i;
                            y = j;
                        }
                        board[i][j] = EMPTY;
                        if (best_score < beta) {
                            beta = best_score;
                        }
                        if (alpha >= beta) {
                            return best_score;
                        }
                    }
                }
            }
        }
        return best_score;
    }
}

// AI下棋
void ai_play() {
    int i, j;
    int best_score = -99999;
    int score;
    int x, y;

    // 极大极小搜索算法
    for (i = 0; i < ROWS; i++) {
        for (j = 0; j < COLS; j++) {
            if (board[i][j] == EMPTY) {
                board[i][j] = ai;
                score = score(i, j, ai);
                if (win(i, j, ai)) {
                    board[i][j] = EMPTY;
                    printf("AI: (%d, %d)\n", j, i);
                    return;
                } else {
                    score += min_max_search(2, -99999, 99999);
                    if (score > best_score) {
                        best_score = score;
                        x = i;
                        y = j;
                    }
                    board[i][j] = EMPTY;
                }
            }
        }
    }

    // 下棋
    board[x][y] = ai;
    printf("AI: (%d, %d)\n", y, x);
}

// 玩家下棋
void player_play() {
    int x, y;
    printf("Player: ");
    scanf("%d %d", &x, &y);
    while (board[x][y] != EMPTY) {
        printf("Invalid move, please try again.\n");
        printf("Player: ");
        scanf("%d %d", &x, &y);
    }
    board[x][y] = player;
}

int main() {
    init_board();
    printf("Please select a player (1:black, 2:white): ");
    scanf("%d", &player);
    while (player != BLACK && player != WHITE) {
        printf("Invalid input, please try again.\n");
        printf("Please select a player (1:black, 2:white): ");
        scanf("%d", &player);
    }
    ai = (player == BLACK) ? WHITE : BLACK;
    print_board();
    while (1) {
        if (player == BLACK) {
            player_play();
            print_board();
            if (win(x, y, player)) {
                printf("Player wins!\n");
                break;
            }
        } else {
            ai_play();
            print_board();
            if (win(x, y, ai)) {
                printf("AI wins!\n");
                break;
            }
        }
        player = (player == BLACK) ? WHITE : BLACK;
    }
    return 0;
}

需要注意的是，以上代码只是一个简单的示例，实际上五子棋AI算法的实现要更加复杂和精细。