指针的引用，交换指针的值

交换两个指针的值
法一-----使用指针的引用
代码如下：

#include<iostream>
using namespace std;

//此函数用于交换指针的值(不是所指对象的值)
void swap(int *&ptr1, int *&ptr2) //参数ptr1,2先与&结合，所以本质上它是一个引用,
{
    
                                      //它引用的对象类型是int *类型，所以它是一个指针的引用
    int *p = ptr1;
    ptr1 = ptr2;
    ptr2 = p;
}

int main()
{
    
    
    int val1 = 10;
    int val2 = 12;
    int *p1 = &val1;
    int *p2 = &val2;
    cout<<"交换之前: "<<endl;
    cout<<"p1 = "<<p1<<" *p1 = "<<*p1<<endl;
    cout<<"p2 = "<<p2<<" *p2 = "<<*p2<<endl;

    swap(p1, p2);

    cout<<"交换之后: "<<endl;
    cout<<"p1 = "<<p1<<" *p1 = "<<*p1<<endl;
    cout<<"p2 = "<<p2<<" *p2 = "<<*p2<<endl;

    return 0;
}

结果如下：