002：难一点的swap

#include <iostream>
using namespace std;

void swap(
 int* &a,int* &b
)
{
    int * tmp = a;
    a = b;
    b = tmp;
}
int main()
{
    int a = 3,b = 5;
    int * pa = & a;
    int * pb = & b;
    swap(pa,pb);
    cout << *pa << "," << * pb;
    return 0;
}