36 lines
791 B
Haskell
36 lines
791 B
Haskell
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module Day6.Main (main) where
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import System.IO
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import Data.List
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main :: IO ()
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main = do
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putStrLn "Day 6"
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handle <- openFile "app/Day6/input" ReadMode
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contents <- hGetContents handle
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let r1 = part1 contents
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putStrLn $ "part 1: " ++ show r1
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let r2 = part2 contents
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putStrLn $ "part 2: " ++ show r2
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distinct xs = length (nub xs) == length xs
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part1 :: String -> Int
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part1 contents = go contents 0
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where
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go [] _ = 0
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go (a:b:c:d:es) n | distinct [a,b,c,d] = n + 4
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go (a:es) n = go es (n + 1)
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part2 :: String -> Int
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part2 contents = go contents 0
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where
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go [] _ = 0
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go (e:es) n = if distinct (e : take 13 es)
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then n + 14
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else go es (n + 1)
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