module Exercise05 where

-- May or may not be useful: computes the logarithm base 2 (rounded down) of the given number.
-- You don't have to move this into the WETT tags if you want to use it.
log2 :: (Integral a, Num b) => a -> b
log2 = let go acc n = if n <= 1 then acc else go (acc + 1) (n `div` 2) in go 0

{-WETT-}

decompose :: [Integer] -> [Integer]
decompose ds
  | 0 `elem` ds = []
  | otherwise = product ds - product [d - mod d 2 | d <- ds] : decompose [div d 2 | d <- ds]

{-TTEW-}