import Data.Ratio

solve :: Ratio Integer -> Integer
solve r
	| d == 1 = n - 1
	| n < d = 1 + solve (1 / r)
	| otherwise = 1 + solve (r - 1)
	where
		d = denominator r;
		n = numerator r;

main = do
	[m, n] <- getLine >>= return . map read . words
	print $ solve (m % n)