c语言决胜21点(一)

好的，让我们开始设计一个用C语言实现的21点游戏吧！

首先，我们需要定义一些基本的规则：

1. 游戏玩家和电脑都会拿到两张牌，牌面点数加起来最接近21点的获胜；
2. 牌面点数从2到10的牌，点数就是牌面显示的数字；
3. J、Q、K的点数都为10点；
4. A牌可以算作1点或11点；
5. 游戏中不能超过21点，超过21点判定为输；
6. 玩家可以选择要牌或停牌，电脑也会自动发牌直到牌面点数大于等于17点。

有了基本规则后，我们就可以开始设计游戏流程了。

首先，我们需要定义一个结构体来表示一张牌：

struct card {
    char* face;  // 牌面，如"2", "J", "Q", "K", "A"
    int value;   // 牌点数，2-10表示2-10点，J、Q、K为10点，A为1或11点
};

然后，我们需要定义一个数组来存储所有的牌：

struct card deck[52] = {
    {"2", 2}, {"3", 3}, {"4", 4}, {"5", 5}, {"6", 6}, {"7", 7},
    {"8", 8}, {"9", 9}, {"10", 10}, {"J", 10}, {"Q", 10}, {"K", 10},
    {"A", 11}, {"2", 2}, {"3", 3}, {"4", 4}, {"5", 5}, {"6", 6}, {"7", 7},
    {"8", 8}, {"9", 9}, {"10", 10}, {"J", 10}, {"Q", 10}, {"K", 10},
    {"A", 11}, {"2", 2}, {"3", 3}, {"4", 4}, {"5", 5}, {"6", 6}, {"7", 7},
    {"8", 8}, {"9", 9}, {"10", 10}, {"J", 10}, {"Q", 10}, {"K", 10},
    {"A", 11}, {"2", 2}, {"3", 3}, {"4", 4}, {"5", 5}, {"6", 6}, {"7", 7},
    {"8", 8}, {"9", 9}, {"10", 10}, {"J", 10}, {"Q", 10}, {"K", 10},
    {"A", 11}
};

接下来，我们需要定义一个函数来随机抽取一张牌：

struct card draw_card() {
    int rand_index = rand() % 52;
    return deck[rand_index];
}

然后，我们需要定义一个函数来计算手中牌的点数：

int calculate_points(struct card* hand, int num_cards) {
    int total_points = 0;
    int num_aces = 0;
    for (int i = 0; i < num_cards; i++) {
        total_points += hand[i].value;
        if (strcmp(hand[i].face, "A") == 0) {
            num_aces++;
        }
    }
    while (num_aces > 0 && total_points > 21) {
        total_points -= 10;
        num_aces--;
    }
    return total_points;
}

接下来，我们需要定义一个函数来判断输赢：

int determine_winner(int player_points, int dealer_points) {
    if (player_points > 21) {
        return -1;  // 玩家输了
    } else if (dealer_points > 21) {
        return 1;   // 玩家赢了
    } else if (player_points > dealer_points) {
        return 1;   // 玩家赢了
    } else if (player_points < dealer_points) {
        return -1;  // 玩家输了
    } else {
        return 0;   // 平局
    }
}

最后，我们需要定义一个主函数来控制游戏流程：

int main() {
    srand(time(NULL));  // 初始化随机数种子
    struct card player_hand[10];  // 玩家手中的牌
    struct card dealer_hand[10];  // 电脑手中的牌
    int num_player_cards = 0;     // 玩家手中牌的数量
    int num_dealer_cards = 0;     // 电脑手中牌的数量
    int player_points = 0;        // 玩家手中牌的点数
    int dealer_points = 0;        // 电脑手中牌的点数

    // 发两张牌给玩家
    player_hand[num_player_cards++] = draw_card();
    player_hand[num_player_cards++] = draw_card();

    // 发两张牌给电脑
    dealer_hand[num_dealer_cards++] = draw_card();
    dealer_hand[num_dealer_cards++] = draw_card();

    // 显示玩家手中的牌和点数
    printf("Your cards:\n");
    for (int i = 0; i < num_player_cards; i++) {
        printf("%s ", player_hand[i].face);
    }
    printf("\n");
    player_points = calculate_points(player_hand, num_player_cards);
    printf("Your points: %d\n", player_points);

    // 玩家选择要牌或停牌
    while (player_points < 21) {
        char choice;
        printf("Do you want to hit (h) or stand (s)? ");
        scanf(" %c", &choice);
        if (choice == 'h') {
            player_hand[num_player_cards++] = draw_card();
            printf("Your cards:\n");
            for (int i = 0; i < num_player_cards; i++) {
                printf("%s ", player_hand[i].face);
            }
            printf("\n");
            player_points = calculate_points(player_hand, num_player_cards);
            printf("Your points: %d\n", player_points);
        } else {
            break;
        }
    }

    // 玩家输赢判断
    if (player_points > 21) {
        printf("Bust! You lose.\n");
        return 0;
    }

    // 电脑自动发牌直到点数大于等于17点
    while (dealer_points < 17) {
        dealer_hand[num_dealer_cards++] = draw_card();
        dealer_points = calculate_points(dealer_hand, num_dealer_cards);
    }

    // 显示电脑手中的牌和点数
    printf("Dealer's cards:\n");
    for (int i = 0; i < num_dealer_cards; i++) {
        printf("%s ", dealer_hand[i].face);
    }
    printf("\n");
    dealer_points = calculate_points(dealer_hand, num_dealer_cards);
    printf("Dealer's points: %d\n", dealer_points);

    // 判断输赢
    int result = determine_winner(player_points, dealer_points);
    if (result == 1) {
        printf("You win!\n");
    } else if (result == -1) {
        printf("You lose!\n");
    } else {
        printf("It's a tie!\n");
    }

    return 0;
}

这就是一个简单的21点游戏的C语言实现，希望能对你有所帮助！