26 lines
751 B
Haskell
26 lines
751 B
Haskell
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-- requires cabal install --lib split Unique
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module Main (main) where
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import Control.Monad (void, when)
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import Data.List (intersect, foldl')
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import Data.List.Split (splitOn)
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import System.Exit (die)
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exampleExpectedOutput = 6
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parseInput :: String -> IO [String]
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parseInput filename = do
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input <- readFile filename
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return $ map (foldl' intersect ['a'..'z'] . lines) $ splitOn "\n\n" input
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compute :: [String] -> Int
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compute = sum . map length
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main :: IO ()
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main = do
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example <- parseInput "example"
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let exampleOutput = compute example
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when (exampleOutput /= exampleExpectedOutput) (die $ "example failed: got " ++ show exampleOutput ++ " instead of " ++ show exampleExpectedOutput)
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input <- parseInput "input"
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print $ compute input
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