Zadatak 10.

#include <bits/stdc++.h>

using namespace std;

int main() {

    string s,t;
    cin >> s >> t;
    int n = s.size();
    string rjesenje = "";
    for(int i = 0; i < n; i++){
            rjesenje+=s[i];
            rjesenje+=t[i];
    }
    cout << rjesenje << endl;
    return 0;
}