#include <iostream>
#include <cstring>
#include <algorithm>
using namespace std;
 
string polacz (string a, string b);
 
 
int main()
{
   int t;
   string a,b;
 
   cin>>t;
   for (int i=0; i<t; ++i)
    {
    cin>>a>>b;
    }
    cout<<(polacz)<<endl;
    return 0;
}
 
string polacz (string a, string b)
{
        int dlugosc;
       {
        if (a.length()<b.length())
        return a;
        else
        return b;
       }
        string nowy= " ";
        for (int i=0; i<dlugosc; ++i)
        {
            nowy+=a[i];
            nowy+=b[i];
 
        }
        return nowy;
 
}
 
 

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