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

namespace _0446
{
    class Program
    {
        static void Main(string[] args)
        {
            var s = Console.ReadLine();
            var chk = "yukicoder";

            for (var i = 0; i < chk.Length; i++)
            {
                if (s[i] == '?')
                {
                    Console.WriteLine(chk[i]);
                    return;
                }
            }
        }
    }
}