#include <bits/stdc++.h>
using namespace std;
 
int main() {
int t;
cin >> t;
while(t--)
{
		string s,p;
		cin >> s >> p;
		char c,d;
		c = s[0];
		d =p[0];
		s[0] = d;
		p[0] = c;
 
		cout << s << " " << p << endl;
 
}
	return 0;
}