import Control.Applicative ((<$>), (<*>))

main :: IO ()
main = solve <$> readLn <*> (map read <$> words <$> getLine) >>= print

solve :: Int -> [Int] -> Int
solve n [a, b, c] = (n `div` a) + (n `div` b) + (n `div` c)
                    - (n `div` ab) - (n `div` bc) - (n `div` ca) + (n `div` abc)
  where ab = lcm a b
        bc = lcm b c
        ca = lcm c a
        abc = lcm ab c