Day 19 - Linen Layout
Megathread guidelines
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FAQ
- What is this?: Here is a post with a large amount of details: https://programming.dev/post/6637268
- Where do I participate?: https://adventofcode.com/
- Is there a leaderboard for the community?: We have a programming.dev leaderboard with the info on how to join in this post: https://programming.dev/post/6631465
2 points
A better version of arrangements using laziness:
arrangements :: [String] -> String -> Int
arrangements atoms molecule = head counts
where
counts = zipWith go (tails molecule) (tails counts)
go [] _ = 1
go m cs = sum $ map (\a -> if a `isPrefixOf` m then cs !! length a else 0) atoms
