import Control.Monad
--import Debug.Trace

saidaikouyakusuu a b r
    | r == 0        = b
    | otherwise     = saidaikouyakusuu b r (b `mod` r)

pyon :: (Integral a) => a -> a -> a
pyon n k
    | (n - k == 0) || (k == 1)  = n - 1
    | r == 1                    = n - 1
    | otherwise                 = n' - 1
    where
        r = saidaikouyakusuu n k (n `mod` k)
        n' = div n r

main = do
    nk <- map (read :: String -> Int) . words <$> getLine
    let
        hasira = [0] ++ take (n - 1) [1,1..]
        n = head nk
        k = last nk
    print $ pyon n k