#include <iostream>
#include <string>

using namespace std;
int main()
{
	string g;
	cin >> g;
	string a = "yukicoder";
	for (int i = 0; i < a.length(); i++)
	{
		if (g[i] == '?')
		{
			cout << a[i] << endl;
			break;
		}
	}
	return 0;
}