-- 間違ったやり方
power :: Integer -> Integer -> Integer
power _ 0       = 1
power n 1       = n
power n x
    | odd x     = n * z * z
    | otherwise = z * z
    where z = power n (x `div` 2)

main :: IO ()
main = do
    [a, x, b, y, c, z] <- map (read :: String -> Integer) . words <$> getLine
    let d = power a x + power b y + power c z
    putStrLn $ if even d then ":-)" else ":-("