using System;
using System.Collections;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using System.Numerics;
using System.Text;
using static System.Console;
using static System.Convert;
using static System.Math;
using static Extentions;

static class Extentions
{
}

static class Program
{
    public static void Main()
    {
        var sw = new StreamWriter(OpenStandardOutput()) { NewLine = "\n" };
        sw.AutoFlush = true;
        SetOut(sw);
        Solve();
    }

    static void Solve()
    {
        var rand = new Random();
        string s;

        while ((s = ReadLine())[0] != 'M')
        {
            var n = int.Parse(s);
            if (n == 20151224)  WriteLine('F');
            else if (n == 0 || rand.Next() % 2 == 0)
            {
                if (rand.Next() % 2 == 0) WriteLine('L');
                else WriteLine('R');
            }
            else WriteLine('F');
        }
    }
}