cs320-factorial-with input

module Factorial (fact) 
   where

fact :: Int -> Int
fact n = prod (down n)

prod :: [Int] -> Int
prod [] = 1
prod (a:as) = a * prod as

down :: Int -> [Int]
down 0 = []
down n = n : down (n-1)

-- END Factorial.hs

main = print(fact 3)