main :: IO ()
main = do
  a <- readLn :: IO Int
  b <- readLn :: IO Int
  c <- readLn :: IO Int 
  d <- readLn :: IO Int
  e <- readLn :: IO Int
  k <- readLn :: IO Int

  let ans = calc e a k
  putStrLn ans
  

calc :: Int -> Int -> Int -> String
calc e a k = do
  case e - a > k of
    True -> ":("
    False ->"Yay!"

