用C++面向对象的思想实现五子棋

在 C 语言中，没有原生的面向对象特性，但可以通过结构体和函数指针等方式来实现类似于面向对象的编程。以下是一个简单的五子棋游戏的实现，其中包含了棋盘、棋子和玩家等相关结构体，以及对应的函数指针实现的方法。

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

#define BOARD_SIZE 15
#define MAX_NAME_LENGTH 50

typedef struct {
    int x;
    int y;
} Point;

typedef struct {
    char name[MAX_NAME_LENGTH];
    char chess;
} Player;

typedef struct {
    char board[BOARD_SIZE][BOARD_SIZE];
    Player *players[2];
    int current_player;
    void (*print_board)(char board[BOARD_SIZE][BOARD_SIZE]);
    void (*place_chess)(char board[BOARD_SIZE][BOARD_SIZE], Point point, char chess);
    int (*check_win)(char board[BOARD_SIZE][BOARD_SIZE], Point point);
    Point (*get_input)(void);
} Game;

void print_board(char board[BOARD_SIZE][BOARD_SIZE]) {
    printf("  ");
    for (int i = 0; i < BOARD_SIZE; i++) {
        printf("%c ", i + 'A');
    }
    printf("\n");
    for (int i = 0; i < BOARD_SIZE; i++) {
        printf("%2d", i + 1);
        for (int j = 0; j < BOARD_SIZE; j++) {
            printf("%c ", board[i][j]);
        }
        printf("\n");
    }
}

void place_chess(char board[BOARD_SIZE][BOARD_SIZE], Point point, char chess) {
    board[point.x][point.y] = chess;
}

int check_win(char board[BOARD_SIZE][BOARD_SIZE], Point point) {
    char chess = board[point.x][point.y];

    // check horizontal
    int count = 1;
    for (int i = point.y - 1; i >= 0; i--) {
        if (board[point.x][i] == chess) {
            count++;
        } else {
            break;
        }
    }
    for (int i = point.y + 1; i < BOARD_SIZE; i++) {
        if (board[point.x][i] == chess) {
            count++;
        } else {
            break;
        }
    }
    if (count >= 5) return 1;

    // check vertical
    count = 1;
    for (int i = point.x - 1; i >= 0; i--) {
        if (board[i][point.y] == chess) {
            count++;
        } else {
            break;
        }
    }
    for (int i = point.x + 1; i < BOARD_SIZE; i++) {
        if (board[i][point.y] == chess) {
            count++;
        } else {
            break;
        }
    }
    if (count >= 5) return 1;

    // check diagonal
    count = 1;
    for (int i = point.x - 1, j = point.y - 1; i >= 0 && j >= 0; i--, j--) {
        if (board[i][j] == chess) {
            count++;
        } else {
            break;
        }
    }
    for (int i = point.x + 1, j = point.y + 1; i < BOARD_SIZE && j < BOARD_SIZE; i++, j++) {
        if (board[i][j] == chess) {
            count++;
        } else {
            break;
        }
    }
    if (count >= 5) return 1;

    // check anti-diagonal
    count = 1;
    for (int i = point.x - 1, j = point.y + 1; i >= 0 && j < BOARD_SIZE; i--, j++) {
        if (board[i][j] == chess) {
            count++;
        } else {
            break;
        }
    }
    for (int i = point.x + 1, j = point.y - 1; i < BOARD_SIZE && j >= 0; i++, j--) {
        if (board[i][j] == chess) {
            count++;
        } else {
            break;
        }
    }
    if (count >= 5) return 1;

    return 0;
}

Point get_input(void) {
    char input[MAX_NAME_LENGTH];
    printf("Please input the position (e.g. \"A1\"): ");
    scanf("%s", input);

    Point point;
    point.x = input[1] - '1';
    point.y = input[0] - 'A';
    return point;
}

void play_game(Game *game) {
    while (1) {
        Player *player = game->players[game->current_player];
        printf("%s's turn (%c)\n", player->name, player->chess);

        Point point = game->get_input();
        if (game->board[point.x][point.y] != ' ') {
            printf("This position has been occupied, please choose another one.\n");
            continue;
        }

        game->place_chess(game->board, point, player->chess);
        game->print_board(game->board);

        if (game->check_win(game->board, point)) {
            printf("%s wins!\n", player->name);
            break;
        }

        game->current_player = 1 - game->current_player;
    }
}

int main() {
    Game game;
    game.current_player = 0;
    game.print_board = print_board;
    game.place_chess = place_chess;
    game.check_win = check_win;
    game.get_input = get_input;

    Player player1 = {"Player 1", 'X'};
    Player player2 = {"Player 2", 'O'};
    game.players[0] = &player1;
    game.players[1] = &player2;

    memset(game.board, ' ', sizeof(game.board));
    game.print_board(game.board);

    play_game(&game);

    return 0;
}

在上述代码中，我们定义了 `Point`、`Player` 和 `Game` 三个结构体，分别表示一个点的坐标、一个玩家和一个游戏。`Game` 结构体中包含了棋盘、两个玩家、当前玩家、打印棋盘、落子、胜利判断和获取输入等函数指针。通过这些函数指针，我们可以方便地实现不同的游戏逻辑。

在 `play_game` 函数中，我们通过循环来进行游戏，每次轮到一个玩家时，获取输入、落子、打印棋盘、判断胜利并切换到下一个玩家。如果有一方胜利，则结束游戏。