指针熟练

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

int main()
{
    int num = 9;
    //变量的地址
    int * ptr_num = &num;
    //指针的地址-定义时需要两个*号
    int ** ptr_num2 = &ptr_num;

    double score[5] = {98,87,65,43,21};
    double * ptr_score;
    //&score[0]数组首元素地址
    ptr_score = &score[0];//等价于ptr_score = score数组首地址

    printf("%p\t%p\n",ptr_score,&score);

    //%p指针占位符  %x16进制占位符
    printf("num变量的地址是：%p\t%x\n",ptr_num,&num);
    printf("%d\n",*ptr_num);

    printf("\n指针ptr_num的地址：%p\n",ptr_num2);
    //如何通过指针的指针，访问到原指针的空间？
    //通过指针的指针，访问原指针指向空间的值时，同样需要两个*号
    printf("\n原空间num对应的值是：%d\n",**ptr_num2);

    return 0;
}