Day 2: Cube Conundrum

Megathread guidelines

  • Keep top level comments as only solutions, if you want to say something other than a solution put it in a new post. (replies to comments can be whatever)
  • Code block support is not fully rolled out yet but likely will be in the middle of the event. Try to share solutions as both code blocks and using something such as https://topaz.github.io/paste/ or pastebin (code blocks to future proof it for when 0.19 comes out and since code blocks currently function in some apps and some instances as well if they are running a 0.19 beta)

FAQ

🔒This post will be unlocked when there is a decent amount of submissions on the leaderboard to avoid cheating for top spots

🔓 Edit: Post has been unlocked after 6 minutes

  • Leo Uino
    2•1 year ago

    Haskell

    A rather opaque parser, but much shorter than I could manage with Parsec.

    import Data.Bifunctor
import Data.List.Split
import Data.Map.Strict (Map)
import qualified Data.Map.Strict as Map
import Data.Tuple

readGame :: String -> (Int, [Map String Int])
readGame = bimap (read . drop 5) (map readPull . splitOn "; " . drop 2) . break (== ':')
  where
    readPull = Map.fromList . map (swap . bimap read tail . break (== ' ')) . splitOn ", "

possibleWith limit = and . Map.intersectionWith (>=) limit

main = do
  games <- map (fmap (Map.unionsWith max) . readGame) . lines <$> readFile "input02"
  let limit = Map.fromList [("red", 12), ("green", 13), ("blue", 14)]
  print $ sum $ map fst $ filter (possibleWith limit . snd) games
  print $ sum $ map (product . snd) games