传递指向指针的引用

#include <iostream> using namespace std;void ptrswap (int *&v1,int *&v2) // 指向指针的引用，{   int *tmp = v2;   v2 = v1;   v1 = tmp;}int main (){int i = 10;int j = 20;int *pi = &i;  // 变换前：*pi指向i，int *pj = &j; // 变换前： *pi指向j，cout << i << "," << j << endl;  // 输出的是10,20cout << *pi << "," << *pj << endl; // 输出是10,20ptrswap(*pi,*pj); // 变换两个指针，cout << i << "," << j << endl; // 输出的10,20cout << *pi << "," << *pj << endl;  // 输出的20,10return 0;}