#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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