30 lines
576 B
Haskell
30 lines
576 B
Haskell
{-# LANGUAGE OverloadedStrings #-}
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module Day15 (parse, solveA) where
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import Data.Text (Text)
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import qualified Data.Text as T
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import Data.Char (ord, isSpace)
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input :: Text
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input = "rn=1,cm-,qp=3,cm=2,qp-,pc=4,ot=9,ab=5,pc-,pc=6,ot=7"
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parse :: Text -> Either String [Text]
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parse = Right . T.splitOn "," . T.filter (not . isSpace)
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hash :: Text -> Int
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hash = foldl step 0 . T.unpack
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where
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step :: Int -> Char -> Int
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step curr = (`rem` 256) . (17 *) . (curr +) . ord
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solveA :: [Text] -> Int
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solveA = sum . map hash
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-- >>> solveA <$> parse input
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-- Right 1320
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