50 lines
1.3 KiB
Haskell
50 lines
1.3 KiB
Haskell
module Day01
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( day01_1,
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day01_2,
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)
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where
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parseInput :: IO [String]
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parseInput = do
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lines <$> readFile "input/day1.txt"
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rotate :: Int -> String -> Int
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rotate n ('L' : xs) = (n - read xs) `mod` 100
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rotate n ('R' : xs) = (n + read xs) `mod` 100
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rotate n _ = n
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rotate' :: Int -> String -> (Int, Int)
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rotate' 0 ('L' : xs) = (negate (read xs) `mod` 100, (read xs + 100) `div` 100 - 1)
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rotate' n ('L' : xs) = ((n - read xs) `mod` 100, (read xs - n + 100) `div` 100)
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rotate' n ('R' : xs) = ((n + read xs) `mod` 100, (read xs + n) `div` 100)
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rotate' n _ = (n, 0)
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getPassword :: Int -> Int -> [String] -> Int
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getPassword pass 0 [] = pass + 1
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getPassword pass _ [] = pass
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getPassword pass 0 (x : xs) = getPassword (pass + 1) (rotate 0 x) xs
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getPassword pass curr (x : xs) = getPassword pass (rotate curr x) xs
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getPassword' :: Int -> Int -> [String] -> Int
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getPassword' pass _ [] = pass
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getPassword' pass curr (x : xs) = getPassword' newPass newVal xs
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where
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(newVal, nZero) = rotate' curr x
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newPass = pass + nZero
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day01_1 :: IO ()
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day01_1 = do
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input <- parseInput
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let result = getPassword 0 50 input
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putStrLn $
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"Day 1, Puzzle 1 solution: "
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++ show result
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day01_2 :: IO ()
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day01_2 = do
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input <- parseInput
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let result = getPassword' 0 50 input
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putStrLn $
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"Day 1, Puzzle 2 solution: "
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++ show result
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