adventofcode16/app/advent06-old.hs

   1 module Main(main) where
   2
   3 import Data.List (transpose)
   4 import Data.Char (isLetter)
   5 import qualified Data.Map.Lazy as Map
   6
   7 main :: IO ()
   8 main = do
   9     text <- readFile "advent06.txt"
  10     let message = lines text
  11     part1 message
  12     part2 message
  13
  14 part1 :: [String] -> IO ()
  15 part1 message = do
  16     print $ map (fst) $ map (mostCommon) $ map (countedLetters) $ transpose message
  17
  18 part2 :: [String] -> IO ()
  19 part2 message = do
  20     print $ map (fst) $ map (leastCommon) $ map (countedLetters) $ transpose message
  21
  22
  23 countedLetters :: String -> Map.Map Char Int
  24 countedLetters name = Map.fromListWith (+) [(c, 1) | c <- filter (isLetter) name]
  25
  26 mostCommon = Map.foldlWithKey (mostCommonP) ('a', 0)
  27
  28 mostCommonP (letter0, count0) letter count
  29     | count > count0 = (letter, count)
  30     | otherwise = (letter0, count0)
  31
  32 leastCommon = Map.foldlWithKey (leastCommonP) ('a', maxBound :: Int)
  33
  34 leastCommonP (letter0, count0) letter count
  35     | count < count0 = (letter, count)
  36     | otherwise = (letter0, count0)