import Control.Monad

main = do
    [a, b, c, d, e, k] <- forM [1 .. 6] $ \i -> do
        read <$> getLine
    putStrLn $ solve a b c d e k

solve :: Int -> Int -> Int -> Int -> Int -> Int -> String
solve a b c d e k | b - a <= k && c - b <= k && d - c <= k && e - d <= k = "Yay!"
                  | otherwise                                            = ":("
