linux kernel data struct : 随机产生一副扑克牌

今天我们来看看，如何随机产生一副扑克牌。

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

typedef enum {
    XIAO_GUI = 1,
    DA_GUI,
    RED_HEART = 3,
    FANG_PIAN,
    MEI_HUA,
    HEI_TAO
}FLOWER_COLOR;

typedef struct {
    FLOWER_COLOR flower;
    int num;
}CARDS;

CARDS cards[54];

void print_card_num(int num)
{
    if(num == 1) printf("%c ",'A');
    else if(num >= 2 && num <= 10) printf("%d ", num);
    else if(num == 11) printf("%c ",'J');
    else if(num == 12) printf("%c ",'Q');
    else if(num == 13) printf("%c ",'K');
}

void wash_cards(int times)
{
    int i, j;
   
    CARDS temp;
   

    //如果不加这个函数，程序每次运行产生的随机数都一样。
    srand((unsigned int)(time(NULL))); //每次运行都足够随机
   
    if(times < 0 || times > 100000)
    {
        printf("wash times err\n");
        return;    
    }
   
    while(times--)
    {
        i = rand()%54;
        j = rand()%54;
       
        memcpy(&temp, &cards[i], sizeof(CARDS));
        memcpy(&cards[i], &cards[j], sizeof(CARDS));
        memcpy(&cards[j], &temp, sizeof(CARDS));
    }
   
    
}

void print_cards(int num)
{
   
    int i;
    int count_line;
   
    printf("\nwash cards:\n");
    for(i = 0, count_line = 1 ; i < num; i++)
    {
      printf("%c",cards[i].flower);
      print_card_num(cards[i].num);
     
      if(count_line == i/12)
      {
          count_line += 1;
          printf("\n");
      }
    }
}

void init_cards(void)
{
    FLOWER_COLOR color;
    int i;
      
    for(color = RED_HEART; color <= HEI_TAO; color++)
    {
        for(i = 1; i <= 13; i++)
        {
            cards[(color-3)*13 + i -1].flower = color;
            cards[(color-3)*13 + i - 1].num = i;
        }
    }
   
    cards[52].flower = XIAO_GUI;
    cards[52].num = 0;
   
    cards[53].flower = DA_GUI;
    cards[53].num = 0;   
   
}

int main(int argc, char *argv[])
{
  init_cards();
  print_cards(54);
  wash_cards(100);
  print_cards(54);
  //printf("%c", FANG_PIAN);
 
  system("PAUSE"); 
  return 0;
}

运行结果如下：

 init cards:....
A 2 3 4 5 6 7 8 9 10 J Q K
A 2 3 4 5 6 7 8 9 10 J Q
K A 2 3 4 5 6 7 8 9 10 J
Q K A 2 3 4 5 6 7 8 9 10
J Q K

wash cards:
5 9 7 7 Q Q 4 8 2 Q 8 9 4
K 5 3 3 5 2 7 3 A 2 8 
10 10 6 4 10 10 9 K K 5 6 J
6 K 3 A J
J Q A 2 8 J
A 7 4 9 6 请按任意键继续. . .