import Data.List
import Data.Tuple
import qualified Data.Set as S

bitn n = sum $ take w $ unfoldr (return . swap . flip divMod 2) n
 where w = ceiling (logBase 2 (fromIntegral n)) + 1

main = readLn >>= putStrLn . maybe "-1" show . sugoroku

sugoroku n = sugoroku' 1 (S.singleton 1)
 where
  sugoroku' s acc
   | S.member n acc = Just s
   | next == acc = Nothing
   | otherwise = sugoroku' (s+1) next
   where
    next = S.union adv bak
    adv = S.filter (\x -> x<=n && x>0) $ S.map (\x -> x + bitn x) acc
    bak = S.filter (\x -> x<=n && x>0) $ S.map (\x -> x - bitn x) acc