杭电2567

#include <iostream>
#include <cstdio>
using namespace std;
int main()
{
	int T;
	string s1,s2;
	scanf("%d",&T);
	while(T--)
	{
		cin>>s1>>s2;
		s1.insert(s1.length()/2,s2);
		cout<<s1<<endl;
	}
return 0;
}