c++实验 引用与指针

#include <iostream>

using namespace std;

void swap(int& a, int& b){
?? ?int tmp;
?? ?tmp = a;
?? ?a = b;
?? ?b = tmp;
}

void swap(int* a, int* b){
?? ?int tmp;
?? ?tmp = *a;
?? ?*a = *b;
?? ?*b = tmp;
}

int main(){
?? ?int a=9;
?? ?int b=10;
?? ?cout<<"a:"<<a<<" "<<"b:"<<b<<endl;
?? ?swap(a, b);
?? ?cout<<"a:"<<a<<" "<<"b:"<<b<<endl;
?? ?swap(&a, &b);
?? ?cout<<"a:"<<a<<" "<<"b:"<<b<<endl;
?? ?
?? ?return 0;
}