import Data.Int

main :: IO ()
main = do
  let ls = [262734068,-1284266430,850241238,1854436759,925227574,1072391605,
            1593098480,753973039,-1320460728,1653753372,1036510631,1372732547,
            2027209822,1573664868, minBound, maxBound]
  print $ (== ls) $ map searchX ls

searchX :: Int32 -> Int32
searchX x
  | p 0 > 0   = f minBound 0
  | otherwise = f 0 maxBound
  where
    f :: Int32 -> Int32 -> Int32
    f l r =
      case p m of
        0  -> m
        1  -> f l m
        -1 -> f (m + 1) r
        _  -> 0
      where
        m = mid l r
    p = aboutX x

aboutX :: Int32 -> Int32 -> Int32
aboutX x a =
  case compare a x of
    EQ -> 0
    GT -> 1
    LT -> -1

mid :: (Integral a) => a -> a -> a
mid x y
  | signum x == signum y = (x + negate y) `div` 2 - negate y
  | otherwise            = (x + y) `div` 2