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

string a = "yukicoder";

int main() {
	string s;
	cin >> s;
	for (int i = 0; i < 9; i++) {
		if (s[i] == '?') {
			cout << a[i] << endl;
			return 0;
		}
	}
	return 0;
}