src/advent04/advent04.hs

   1 import Data.List (sort, nub)
   2
   3 main :: IO ()
   4 main = do
   5         text <- readFile "data/advent04.txt"
   6         let passphrases = map words $ lines text
   7         print $ part1 passphrases
   8         print $ part2 passphrases
   9
  10 part1 :: [[String]] -> Int
  11 part1 = length . filter (not . containsDuplicates)
  12
  13 part2 :: [[String]] -> Int
  14 part2 = length . filter (not . containsAnagrams)
  15
  16 containsDuplicates :: [String] -> Bool
  17 containsDuplicates passphrase = (length passphrase) /= (length $ nub passphrase)
  18
  19 containsAnagrams :: [String] -> Bool
  20 containsAnagrams = containsDuplicates . (map sort)