import Data.List
import Control.Monad

main = do
 vs <- sort . map read . words <$> getLine
 print (ita vs)

ita vs@[v1,v2,v3,v4] = 
 max 4 $ min ((+3) $ minimum' $ concat [nboards v1 v2 v3, nboards v1 v3 v4, nboards v2 v3 v4]) (2 + div vx gm + div vy gm)
  where
   (gm,(vx,vy)) = maximum [(gcd vx vy, (vx,vy)) | vx <- vs, vy <- (delete vx vs)]
   minimum' xs = if null xs then 0 else minimum xs

nboards x y l = do
 i <- [1 .. div l x]
 j <- [1 .. div (l - i*x) y]
 guard (i*x + j*y == l)
 return (i + j)