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

class Program
{
    public void Proc()
    {

        int redCount = 0;
        for (int i = 0; i < 3; i++)
        {
            if(Reader.ReadLine().Equals("RED")) {
                redCount++;
            }
        }

        string ans = "BLUE";
        if (redCount >= 2)
        {
            ans = "RED";
        }

        Console.WriteLine(ans);

    }








    public class Reader
    {
        public static bool IsDebug = false;
        private static String PlainInput = @"


RED
RED
BLUE



";
        private static System.IO.StringReader Sr = null;
        public static string ReadLine()
        {
            if (IsDebug)
            {
                if (Sr == null)
                {
                    Sr = new System.IO.StringReader(PlainInput.Trim());
                }
                return Sr.ReadLine();
            }
            else
            {
                return Console.ReadLine();
            }
        }
    }
    static void Main()
    {
#if DEBUG
        Reader.IsDebug = true;
#endif
        Program prg = new Program();
        prg.Proc();
    }
}