even' :: String -> String
even' s = [s !! (2*i) | i<-[0..length s],2*i<length s]
odd' ::String -> String
odd' s = [s !! (2*i+1) | i<-[0..length s],2*i+1 < length s]



main = do
    s <- getLine
 --   putStrLn (even' s)
--    putStrLn (odd' s)
    if 'L' `elem` (even' s) || 'R' `elem` (odd' s)
        then putStrLn ("No")
        else putStrLn  ("Yes")
