#include <bits/stdc++.h>
using namespace std;

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

	string ex = "yukicoder";
	for (int i = 0; i < s.size(); i++) {
		if (s.at(i) == '?') {
			cout << ex.at(i) << endl;
			return 0;
		}
	}
}