import Control.Monad (replicateM)

main :: IO ()
main = do
  [a,_,_,_,e,k] <- map (read :: String -> Int) <$> getNLine_ 6
  if e - a <= k then putStrLn "Yay!" else putStrLn ":("

getNLine_ :: Int -> IO [String]
getNLine_ n = replicateM n getLine