import Data.Bool (bool)

main :: IO ()
main = do
  a <- read <$> getLine :: IO Int
  b <- read <$> getLine :: IO Int
  c <- read <$> getLine :: IO Int
  d <- read <$> getLine :: IO Int
  e <- read <$> getLine :: IO Int
  k <- read <$> getLine :: IO Int
  putStrLn . bool ":(" "Yay!" $ e - a <= k
