二级指针理解

#include<stdio.h>
int main()
{
    int num = 5;
    int *p_num = &num;
    int **pp_num = &p_num;
    printf("%d\n", num);
    printf("%d\n", *p_num);
    printf("%p %p\n", &num, p_num);
    printf("%d\n", **pp_num);
    printf("%p %p %p\n", &p_num, pp_num, *pp_num);
    return 0;
}