import Control.Applicative ((<$>))

main :: IO ()
main = do
  solve <$> getl read >>= print

solve :: Int -> Int
solve = f 0
  where
    f c x = if x == 1 then c
            else let (q, r) = x `divMod` 2
                 in f (c + 1) (q + r)

getl :: (String -> a) -> IO a
getl f = f <$> getLine