evens :: [a] -> [a]
evens (x:xs) = x:odds xs
evens _ = []

odds :: [a] -> [a]
odds (_:xs) = evens xs
odds _ = []

easyToTap :: String -> Bool
easyToTap s = isOddsEasy s && isEvensEasy s
    where
        isOddsEasy  s = and . map (\c -> c == 'L' || c == 'U' || c == 'D') $ odds s
        isEvensEasy s = and . map (\c -> c == 'R' || c == 'U' || c == 'D') $ evens s

main = do
    easy <- easyToTap <$> getLine
    putStrLn $ if easy then "Yes" else "No"