local isend = "Merry Christmas!"
local function query(str)
  io.write(str .. "\n")
  io.flush()
  local ret = io.read("*l")
  if ret == isend then os.exit() end
  return ret
end
local s = io.read()
while s == "0" do
  s = query("L")
end
while s ~= "0" do
  s = query("F")
end
while s == "0" do
  s = query("R")
end
while true do
  if s == "0" then
    s = query("L")
    if s == "0" then
      while s == "0" do
        s = query("R")
      end
    end
    s = query("F")
  else
    s = query("L")
    if s == "0" then
      s = query("R")
      s = query("F")
    else
      s = query("F")
    end
  end
end