#include <iostream>
#include <algorithm>
#include <string>
#include <cstdio>
using namespace std;

int main()
{
    string s; cin >> s;

    string t = "yukicoder";
    for (int i = 0; i < s.size(); i++) {
        if (s[i] == '?') return cout << t[i] << endl, 0;
    }

    return 0;
}