import sys

sys.setrecursionlimit(10 ** 6)
from bisect import *
from collections import *
from heapq import *

def II(): return int(sys.stdin.readline())
def MI(): return map(int, sys.stdin.readline().split())
def LI(): return list(map(int, sys.stdin.readline().split()))
def SI(): return sys.stdin.readline()[:-1]
def LLI(rows_number): return [LI() for _ in range(rows_number)]
int1 = lambda x: int(x) - 1
def MI1(): return map(int1, sys.stdin.readline().split())
def LI1(): return list(map(int1, sys.stdin.readline().split()))
p2D = lambda x: print(*x, sep="\n")
dij = [(0, 1), (1, 0), (0, -1), (-1, 0)]

def main():
    def check(ret):
        while ret == "20151224":
            print("F", flush=True)
            ret = input()
        if ret == "Merry Christmas!":
            exit()

    ret=input()
    check(ret)
    while ret!="0":
        print("F", flush=True)
        ret = input()
        check(ret)
    print("L", flush=True)
    ret = input()
    check(ret)

    while 1:
        print("R",flush=True)
        ret=input()
        check(ret)
        while ret=="0":
            print("L",flush=True)
            ret=input()
            check(ret)
        print("F",flush=True)
        ret = input()
        check(ret)

main()