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