import Control.Applicative
import Data.Bits
import Data.Char
import Data.List
import Data.Tuple

main :: IO ()
main = mapM_ putStrLn $ [f534, f534', g534] <*> [0..10]

f534 :: Integral a => a -> String
f534 =
  flip (map . (((intToDigit . signum) .) . (.&.) . fromIntegral))
    =<< takeWhile (not . (== 0)) . iterate (`div` 2) .
        bit . floorLogBase2FromIntegral .
        (if' id (const nnErr) =<< (>= 0))

f534' :: Integral a => a -> String
f534' =
  ((map intToDigitFromIntegral . snd) .) . flip (mapAccumR divMod)
    =<< flip replicate 2 . succ . floorLogBase2FromIntegral .
        (if' id (const nnErr) =<< (>= 0))

g534 :: Integral a => a -> String
g534 = if' (const "0") (map intToDigitFromIntegral . reverse . unfoldr (if' (const Nothing) (Just . swap . (`divMod` 2)) =<< (== 0)) . (if' id (const nnErr) =<< (>= 0))) =<< (== 0)

nnErr :: e
nnErr = error "applied to negative number"

floorLogBase2FromIntegral :: (Integral a, Integral b) => a -> b
floorLogBase2FromIntegral = floor . logBase 2 . fromIntegral

intToDigitFromIntegral :: Integral a => a -> Char
intToDigitFromIntegral = intToDigit . fromIntegral

if' :: a -> a -> Bool -> a
if' f g p = if p then f else g