C/C++ 指向指針的指針

實例代碼如下

#include <stdio.h>

int main()
{
    int a = 100;
    int *p = &a;
    int **p2 = &p;
    printf("&a   = %d\n",&a);
    printf("p    = %d\n",p);
    printf("*p   = %d\n",*p);
    printf("p2   = %d\n",p2);
    printf("*p2  = %d\n",*p2);
    printf("**p2 = %d\n",**p2);

    return 0;
}

輸出結果：

&a   = 1725882484
p    = 1725882484
*p   = 100
p2   = 1725882488
*p2  = 1725882484
**p2 = 100

&a是變量a的內存地址，p = &a,也是內存地址，*p = 100 ，是a的值，p2不知道什麼鬼，*p2 = p = &a ,是內存地址，**p2=100是a的值