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