f1:

#include<bits/stdc++.h>
using namespace std;
int main()
{
    int a,b;
    cin>>a>>b;
    swap(a,b);
    cout<<a<<" "<<b;
    return 0;
}

f2:

#include<bits/stdc++.h>
using namespace std;
int main()
{
    int a,b;
    cin>>a>>b;
    cout<<b<<" "<<a;
    return 0;
}

f3:

#include<bits/stdc++.h>
using namespace std;
int main()
{
    int a,b,c;
    cin>>a>>b;
    c=a;
    a=b;
    b=c;
    cout<<a<<" "<<b;
    return 0;
}