-- Your code here!
f :: (Int, Char) -> Bool
f (i, c) = ((mod i 2 == 0) && not (c == 'L')) || ((mod i 2 == 1) && not (c == 'R'))

g :: Bool -> String
g True = "Yes"
g False = "No"

main = do
    str <- getLine
    putStrLn $ g $ foldr (&&) True $ map f (zip [0..] str)
