using System;
using System.Collections.Generic;
using System.Linq;

class Program
{
    public void Solve()
    {
        const string yuki = "yukicoder";
        string S = Console.ReadLine();

        Console.WriteLine(yuki.Substring(S.IndexOf('?'), 1));
    }

    static void Main()
    {
        var solver = new Program();
        solver.Solve();
    }
}