2022/01/Main.idr

import System.File.ReadWrite
import Data.String
import Data.List1

parseInput : String -> List1 (List Int)
parseInput input =
  let inputLines = lines input
      grouped = split (== "") inputLines
  in map (map cast) grouped

part1 : String -> IO ()
part1 input =
 let parsed = parseInput input
     totals = map (foldr (+) 0) parsed
 in do printLn $ foldr max 0 totals

part2 : String -> IO ()
part2 input =
 let parsed = parseInput input
     totals = map (foldr (+) 0) parsed
     sorted = reverse . sort . forget $ totals

main : IO ()
main = do file <- readFile "input"
          case file of
            Right content =>
                do putStr "Part 1: "
                   part1 content
                   putStr "Part 2: "
                   part2 content
            Left err => printLn err