unzipwith.hs

module Main where

import Util (unzipWith)

count :: [(Bool, Bool)]
count = do
    d1 <- [1..8]
    d2 <- [1..8]
    d3 <- [1..8]
    d4 <- [1..8]
    let sum3ok = sum([d1, d2, d3]) == 8
    let sum4ok = sum([d1, d2, d4]) == 8
    return (sum3ok, sum4ok)

-- the original definition
met = length $ filter id $ map (uncurry (||)) count

-- with unzipWith
met' = length $ filter id $ unzipWith (||) count


main :: IO ()
main = do
  print met
  print met'