写一个人机对决的井字棋C++程序

好的，以下是一个简单的人机对战的井字棋C++程序：

#include <iostream>
#include <vector>
#include <ctime>
#include <cstdlib>

using namespace std;

// 定义棋盘大小
const int BOARD_SIZE = 3;

// 定义棋子类型
const char EMPTY = '-';
const char HUMAN = 'X';
const char COMPUTER = 'O';

// 定义游戏状态
enum GameState {
    PLAYING, DRAW, HUMAN_WIN, COMPUTER_WIN
};

// 初始化棋盘
void initBoard(vector<vector<char>>& board) {
    board.resize(BOARD_SIZE);
    for (int i = 0; i < BOARD_SIZE; ++i) {
        board[i].resize(BOARD_SIZE, EMPTY);
    }
}

// 打印棋盘
void printBoard(const vector<vector<char>>& board) {
    for (int i = 0; i < BOARD_SIZE; ++i) {
        for (int j = 0; j < BOARD_SIZE; ++j) {
            cout << board[i][j] << " ";
        }
        cout << endl;
    }
    cout << endl;
}

// 获取空闲位置
vector<pair<int, int>> getEmptyCells(const vector<vector<char>>& board) {
    vector<pair<int, int>> emptyCells;
    for (int i = 0; i < BOARD_SIZE; ++i) {
        for (int j = 0; j < BOARD_SIZE; ++j) {
            if (board[i][j] == EMPTY) {
                emptyCells.push_back(make_pair(i, j));
            }
        }
    }
    return emptyCells;
}

// 判断是否胜利
bool isWin(const vector<vector<char>>& board, char player) {
    // 判断行
    for (int i = 0; i < BOARD_SIZE; ++i) {
        bool win = true;
        for (int j = 0; j < BOARD_SIZE; ++j) {
            if (board[i][j] != player) {
                win = false;
                break;
            }
        }
        if (win) {
            return true;
        }
    }
    // 判断列
    for (int j = 0; j < BOARD_SIZE; ++j) {
        bool win = true;
        for (int i = 0; i < BOARD_SIZE; ++i) {
            if (board[i][j] != player) {
                win = false;
                break;
            }
        }
        if (win) {
            return true;
        }
    }
    // 判断对角线
    bool win = true;
    for (int i = 0; i < BOARD_SIZE; ++i) {
        if (board[i][i] != player) {
            win = false;
            break;
        }
    }
    if (win) {
        return true;
    }
    win = true;
    for (int i = 0; i < BOARD_SIZE; ++i) {
        if (board[i][BOARD_SIZE - i - 1] != player) {
            win = false;
            break;
        }
    }
    if (win) {
        return true;
    }
    return false;
}

// 获取下一步最优位置
pair<int, int> getBestMove(const vector<vector<char>>& board) {
    vector<pair<int, int>> emptyCells = getEmptyCells(board);
    // 如果棋盘已满
    if (emptyCells.empty()) {
        return make_pair(-1, -1);
    }
    // 如果有下一步可以直接胜利的位置
    for (int i = 0; i < emptyCells.size(); ++i) {
        int x = emptyCells[i].first;
        int y = emptyCells[i].second;
        vector<vector<char>> nextBoard = board;
        nextBoard[x][y] = COMPUTER;
        if (isWin(nextBoard, COMPUTER)) {
            return make_pair(x, y);
        }
    }
    // 如果对手有下一步可以直接胜利的位置，则堵住
    for (int i = 0; i < emptyCells.size(); ++i) {
        int x = emptyCells[i].first;
        int y = emptyCells[i].second;
        vector<vector<char>> nextBoard = board;
        nextBoard[x][y] = HUMAN;
        if (isWin(nextBoard, HUMAN)) {
            return make_pair(x, y);
        }
    }
    // 否则随机下一步
    int index = rand() % emptyCells.size();
    return emptyCells[index];
}

int main() {
    srand(time(0));
    vector<vector<char>> board;
    initBoard(board);
    GameState state = PLAYING;
    char currentPlayer = HUMAN;
    while (state == PLAYING) {
        if (currentPlayer == HUMAN) {
            cout << "Human's turn:" << endl;
            printBoard(board);
            int x, y;
            cout << "Please enter row and column (1-" << BOARD_SIZE << "): ";
            cin >> x >> y;
            --x;
            --y;
            if (x < 0 || x >= BOARD_SIZE || y < 0 || y >= BOARD_SIZE || board[x][y] != EMPTY) {
                cout << "Invalid move!" << endl;
                continue;
            }
            board[x][y] = HUMAN;
            if (isWin(board, HUMAN)) {
                state = HUMAN_WIN;
            }
            currentPlayer = COMPUTER;
        } else {
            cout << "Computer's turn:" << endl;
            printBoard(board);
            pair<int, int> move = getBestMove(board);
            if (move.first == -1 && move.second == -1) {
                state = DRAW;
            } else {
                board[move.first][move.second] = COMPUTER;
                if (isWin(board, COMPUTER)) {
                    state = COMPUTER_WIN;
                }
                currentPlayer = HUMAN;
            }
        }
    }
    printBoard(board);
    if (state == DRAW) {
        cout << "Draw!" << endl;
    } else if (state == HUMAN_WIN) {
        cout << "Human wins!" << endl;
    } else if (state == COMPUTER_WIN) {
        cout << "Computer wins!" << endl;
    }
    return 0;
}

这个程序实现了简单的人机对战，玩家使用 X 表示，电脑使用 O 表示，玩家先手。程序会提示玩家输入行和列，玩家输入后程序会判断合法性并在棋盘中标记。当有一方胜利或者棋盘已满时，游戏结束并输出结果。在电脑回合，程序会根据当前棋盘状态选择最优位置进行落子。