python 代码运用α-β剪枝算法实现五子棋小游戏

好的，我可以为您提供一个基于 Python 的五子棋小游戏实现，使用了 α-β剪枝算法来实现电脑的 AI 策略。

首先，为了实现五子棋，我们需要一个棋盘，可以使用二维数组来表示：

board = [[0 for i in range(15)] for j in range(15)]

其中，0 表示该位置为空，1 表示该位置为黑子，2 表示该位置为白子。

接着，我们需要实现落子函数，来让玩家和电脑下棋：

def move(board, row, col, player):
    if board[row][col] != 0:
        return False
    board[row][col] = player
    return True

其中，`player` 参数表示玩家或电脑，1 表示玩家，2 表示电脑。

接下来，我们需要实现电脑的 AI 策略，使用 α-β剪枝算法来优化搜索：

def alphabeta(board, depth, alpha, beta, player):
    if depth == 0:
        return evaluate(board, player)
    if player == 2:
        best_score = -999999
        for row in range(15):
            for col in range(15):
                if board[row][col] == 0:
                    board[row][col] = player
                    score = alphabeta(board, depth - 1, alpha, beta, 1)
                    board[row][col] = 0
                    best_score = max(best_score, score)
                    alpha = max(alpha, score)
                    if beta <= alpha:
                        break
        return best_score
    else:
        best_score = 999999
        for row in range(15):
            for col in range(15):
                if board[row][col] == 0:
                    board[row][col] = player
                    score = alphabeta(board, depth - 1, alpha, beta, 2)
                    board[row][col] = 0
                    best_score = min(best_score, score)
                    beta = min(beta, score)
                    if beta <= alpha:
                        break
        return best_score

其中，`depth` 参数表示搜索的深度，`alpha`、`beta` 参数分别表示 α、β 值。

最后，我们需要实现评估函数，来评估当前棋盘的得分：

def evaluate(board, player):
    score = 0
    for row in range(15):
        for col in range(15):
            if board[row][col] == player:
                score += 1
    return score

最后，我们可以将上述函数整合到一个完整的程序中，来实现五子棋小游戏：

import random

board = [[0 for i in range(15)] for j in range(15)]

def move(board, row, col, player):
    if board[row][col] != 0:
        return False
    board[row][col] = player
    return True

def alphabeta(board, depth, alpha, beta, player):
    if depth == 0:
        return evaluate(board, player)
    if player == 2:
        best_score = -999999
        for row in range(15):
            for col in range(15):
                if board[row][col] == 0:
                    board[row][col] = player
                    score = alphabeta(board, depth - 1, alpha, beta, 1)
                    board[row][col] = 0
                    best_score = max(best_score, score)
                    alpha = max(alpha, score)
                    if beta <= alpha:
                        break
        return best_score
    else:
        best_score = 999999
        for row in range(15):
            for col in range(15):
                if board[row][col] == 0:
                    board[row][col] = player
                    score = alphabeta(board, depth - 1, alpha, beta, 2)
                    board[row][col] = 0
                    best_score = min(best_score, score)
                    beta = min(beta, score)
                    if beta <= alpha:
                        break
        return best_score

def evaluate(board, player):
    score = 0
    for row in range(15):
        for col in range(15):
            if board[row][col] == player:
                score += 1
    return score

def play():
    while True:
        print("请输入您要下棋的位置，用逗号分隔行列，如 1,1 表示第一行第一列：")
        row, col = map(int, input().split(","))
        if move(board, row - 1, col - 1, 1):
            print("您下了一步棋，当前棋盘：")
            for row in board:
                print(row)
            if evaluate(board, 1) >= 5:
                print("您赢了！")
                break
            print("电脑正在思考，请稍等...")
            best_score = -999999
            best_row = -1
            best_col = -1
            for row in range(15):
                for col in range(15):
                    if board[row][col] == 0:
                        board[row][col] = 2
                        score = alphabeta(board, 3, -999999, 999999, 1)
                        board[row][col] = 0
                        if score > best_score:
                            best_score = score
                            best_row = row
                            best_col = col
            move(board, best_row, best_col, 2)
            print("电脑下了一步棋，当前棋盘：")
            for row in board:
                print(row)
            if evaluate(board, 2) >= 5:
                print("电脑赢了！")
                break

if __name__ == "__main__":
    play()

在上述程序中，我们使用了 `play()` 函数来启动五子棋游戏，玩家先手，电脑后手，电脑使用 α-β剪枝算法来实现 AI 策略。