#include <iostream>
#include <string>
using namespace std;

int main(){
    int n; cin >> n;
    string s[n];
    string t[n];

    for(int i = 0; i < n; i++) cin >> s[i] >> t[i];

    for(int i = 0; i < n; i++){
        if(s[i] != t[i]){
            cout << i+1 << endl;
            cout << s[i] << endl;
            cout << t[i] << endl;
        }
    }


    return 0;
}