下面是一个简陋的猜字游戏，玩了一会儿，发现自己打不过自己写的游戏，除非赢了就跑，最高分没有过1000。

说明：srand(time(NULL))和rand()，srand，time和rand都是函数，其中srand和rand配对使用，srand是start random，也就是随机数的初始化，time函数中的NULL表示获取系统时间，所以整个意思是：以系统时间开始初始化，然后获取随机数。随机数结果是一个整数。

#include <stdio.h>

#include <stdlib.h>

#include <time.h>

int cash = 100;

void play(int bet) {

    char *C = (char *) malloc(sizeof(char) * 100);

    C[0] = 'J';

    C[1] = 'Q';

    C[2] = 'K';

    printf("Shuffling... \n");

    srand(time(NULL));

    int i;

    for (i = 0; i < 5; i++) {

        int x = rand() % 3;

        int y = rand() % 3;

        char temp = C[x];

        C[x] = C[y];

        C[y] = temp;

    }

    int playersGuess;

    printf("What's your guess for the Queen's position? 1, 2 or 3: ");

    scanf("%d", &playersGuess);

    if (C[playersGuess - 1] == 'Q') {

        cash = cash + bet * 3;

        printf("You win!, the result is: %c %c %c\n", C[0], C[1], C[2]);

        printf("Your money left is $ %d.\n", cash);

    } else {

        cash = cash - bet * 3;

        printf("You lose the bet, the result is: %c %c %c\n", C[0], C[1], C[2]);

        printf("Your money left is $ %d.\n", cash);

    }

    free(C);

}

void main(void) {

    int bet;

    printf("Welcome to the virtual Casino!\n");

    printf("The total cash you have from the start is $%d.\n", cash);

    while (cash > 0) {

        printf("Please enter your bet: $ ");

        scanf("%d", &bet);

        if (bet <= 0) break;

        else if (bet > cash) {

            printf("Error. The bet is bigger than your cash.");

            break;

        }

        play(bet);

    }

    printf("You lost the game. \n");

}

有时间加入一个重新开始的功能，可玩性会高一些。