C 程序显示指针与指针之间的关系
cserver side programmingprogramming更新于 2024/11/5 14:59:00
在 C 编程语言中，指针与指针或双指针是保存另一个指针地址的变量。
声明
下面给出了指向指针 − 的声明
datatype ** pointer_name;
例如，int **p;
这里，p 是一个指向指针的指针。
初始化
‘&’ 用于初始化。
例如，
int a = 10; int *p; int **q; p = &a;
访问
间接运算符 (*) 用于访问
示例程序
以下是双指针的 C 程序 −
#include<stdio.h>
main ( ){
int a = 10;
int *p;
int **q;
p = &a;
q = &p;
printf("a =%d ",a);
printf(" a value through pointer = %d", *p);
printf(" a value through pointer to pointer = %d", **q);
}
输出
当执行上述程序时，它会产生以下结果 −
a=10 a value through pointer = 10 a value through pointer to pointer = 10
示例
现在，考虑另一个 C 程序，该程序显示了指针与指针之间的关系。
#include<stdio.h>
void main(){
//声明变量和指针//
int a=10;
int *p;
p=&a;
int **q;
q=&p;
//打印所需 O/p//
printf("Value of a is %d
",a);//10//
printf("Address location of a is %d
",p);//address of a//
printf("Value of p which is address location of a is %d
",*p);//10//
printf("Address location of p is %d
",q);//address of p//
printf("Value at address location q(which is address location of p) is %d
",*q);//address of a//
printf("Value at address location p(which is address location of a) is %d
",**q);//10//
}
输出
当执行上述程序时，它会产生以下结果 −
Value of a is 10 Address location of a is 6422036 Value of p which is address location of a is 10 Address location of p is 6422024 Value at address location q(which is address location of p) is 6422036 Value at address location p(which is address location of a) is 10
