#include <bits/stdc++.h>
using namespace std;

int main()
{
    int a , b , t;
    a = 10 , b = 20;
    cout << "a=" << a << " b=" << b << endl;
    t = a;
    a = b;
    b = t;
    cout << "a=" << a << " b=" << b << endl; 
	return 0;
}