check :: String -> Bool
check "resare" = True
check "esare" = True
check "remaerd" = True
check "maerd" = True
check (c1:c2:c3:c4:c5:c6:c7:cs)
    | head5 == "resar" = if c6 == 'e'
                         then check (c7:cs)
                         else False
    | head5 == "esare" = check $ c6:c7:cs
    | head5 == "remae" = if (c6:c7:[] == "rd")
                         then (check cs)
                         else False
    | head5 == "maerd" = check $ c6:c7:cs
    | otherwise = False
    where head5 = c1:c2:c3:c4:c5:[]
check _ = False
 
main :: IO ()
main = do
    sentence <- getLine :: IO String
    putStr $ if (check $ reverse sentence) then "YES" else "NO"