用c++编程一个功能齐全的数独游戏

以下是一个基于 C++ 的数独游戏代码，包含生成数独题目、解题算法、用户界面等功能。代码中使用了回溯法求解数独，生成数独题目使用了随机填数算法。

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

using namespace std;

// 定义数独的数据结构
const int N = 9;
int board[N][N];

// 打印数独
void print_board() {
    cout << "-------------------------" << endl;
    for (int i = 0; i < N; i++) {
        for (int j = 0; j < N; j++) {
            if (j % 3 == 0) cout << "| ";
            cout << board[i][j] << " ";
        }
        cout << "|" << endl;
        if (i % 3 == 2) cout << "-------------------------" << endl;
    }
}

// 检查数字 num 是否可以填入行 row，列 col，九宫格
bool check_num(int num, int row, int col) {
    // 检查行和列
    for (int i = 0; i < N; i++) {
        if (board[row][i] == num || board[i][col] == num) {
            return false;
        }
    }
    // 检查九宫格
    int row_start = (row / 3) * 3;
    int col_start = (col / 3) * 3;
    for (int i = row_start; i < row_start + 3; i++) {
        for (int j = col_start; j < col_start + 3; j++) {
            if (board[i][j] == num) {
                return false;
            }
        }
    }
    return true;
}

// 回溯法填数
bool solve_board(int row, int col) {
    if (row == N) return true;
    if (col == N) return solve_board(row + 1, 0);
    if (board[row][col] != 0) return solve_board(row, col + 1);
    for (int num = 1; num <= 9; num++) {
        if (check_num(num, row, col)) {
            board[row][col] = num;
            if (solve_board(row, col + 1)) {
                return true;
            }
            board[row][col] = 0;
        }
    }
    return false;
}

// 随机生成数独题目
void generate_board(int num) {
    memset(board, 0, sizeof(board));
    solve_board(0, 0);
    srand(time(NULL));
    for (int i = 0; i < num; i++) {
        int row = rand() % N;
        int col = rand() % N;
        while (board[row][col] == 0) {
            row = rand() % N;
            col = rand() % N;
        }
        int temp = board[row][col];
        board[row][col] = 0;
        vector<pair<int, int>> v;
        bool has_sol = false;
        for (int num = 1; num <= 9; num++) {
            if (check_num(num, row, col)) {
                board[row][col] = num;
                if (solve_board(0, 0)) {
                    v.push_back(make_pair(row, col));
                    has_sol = true;
                }
            }
        }
        if (!has_sol) {
            board[row][col] = temp;
        } else {
            int index = rand() % v.size();
            for (int i = 0; i < v.size(); i++) {
                if (i == index) continue;
                board[v[i].first][v[i].second] = 0;
            }
        }
    }
}

// 检查数独是否填满
bool is_full() {
    for (int i = 0; i < N; i++) {
        for (int j = 0; j < N; j++) {
            if (board[i][j] == 0) {
                return false;
            }
        }
    }
    return true;
}

// 检查数独是否填写正确
bool check_board() {
    for (int i = 0; i < N; i++) {
        for (int j = 0; j < N; j++) {
            int num = board[i][j];
            board[i][j] = 0;
            if (num != 0 && !check_num(num, i, j)) {
                board[i][j] = num;
                return false;
            }
            board[i][j] = num;
        }
    }
    return true;
}

// 用户界面
void play_game() {
    while (true) {
        cout << "=========================" << endl;
        cout << "Welcome to Sudoku Game!" << endl;
        cout << "1. New game" << endl;
        cout << "2. Check answer" << endl;
        cout << "3. Quit" << endl;
        cout << "=========================" << endl;
        int choice;
        cin >> choice;
        switch (choice) {
            case 1: {
                cout << "Please input the number of blanks: ";
                int num;
                cin >> num;
                generate_board(num);
                print_board();
                break;
            }
            case 2: {
                if (is_full()) {
                    if (check_board()) {
                        cout << "Congratulations! You solved the Sudoku!" << endl;
                    } else {
                        cout << "Sorry, your answer is wrong." << endl;
                    }
                } else {
                    cout << "Please finish the Sudoku first." << endl;
                }
                break;
            }
            case 3: {
                cout << "Goodbye!" << endl;
                return;
            }
            default: {
                cout << "Invalid input, please try again." << endl;
                break;
            }
        }
    }
}

int main() {
    play_game();
    return 0;
}

该代码实现了数独游戏的基本功能，包括生成数独题目、回溯法求解、随机生成空格、用户界面等功能。您可以按照自己的需求进行修改和完善。