#include <stdio.h>
int main()
{
    /*********************************************
     *
     *  %d int
     *  %f float\double
     *  %ld long
     *  %lld long long
     *  %c char
     *  %s 字符串
     *  %zd  unsigned long
     *
     *  清空指针：
     *      int a = 10;
     *      int *p = &a;
     *      //1、
     *      // p = 0;
     *      //2、注意不是null
     *      //p = NULL;
     *  清空指针后指针将不能再访问指向的区域
     *
     **********************************************/

       int a = 10;
       int *p = &a;
       printf("a is %d\n",*p);
       //p = 0;
       //p = NULL;
           return 0;
}