#include <iostream>
#include <cstring>
using namespace std;
#define T_SIZE 1001
char* string_merge(char* m, char* n)
{
int dlugosc=strlen(m);
int dlugosc2=strlen(n);
int y;
if(dlugosc<=dlugosc2)y=dlugosc-1;
if(dlugosc2<=dlugosc)y=dlugosc2-1;
for(int i=0; i<=y; i++)
{
cout<<m[i];
cout<<n[i];
}
cout<<endl;
return m;
}
int main()
{
int t;
char S1[T_SIZE], S2[T_SIZE], *S;
cin>>t;
cin.getline(S1, T_SIZE);
while(t)
{
cin.getline(S1, T_SIZE,' ');
cin.getline(S2, T_SIZE);
S=string_merge(S1,S2);
t--;
}
return 0;
}
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