solve :: String -> String
solve [] = "Yes"
solve [x] = if x `elem` ['R', 'U', 'D'] then "Yes" else "No"
solve (x:y:xs) = if x `elem` ['R', 'U', 'D'] && y `elem` ['L', 'U', 'D'] then solve xs else "No"

main = getLine >>= putStrLn . solve
