31 lines
729 B
Haskell
31 lines
729 B
Haskell
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module Day02 (parse, solveA, solveB) where
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splitOn :: (Eq a) => a -> [a] -> [[a]]
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splitOn _ [] = []
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splitOn delimiter xs =
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let (before, remainder) = break (== delimiter) xs
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in before : case remainder of
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[] -> []
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_ : rest -> splitOn delimiter rest
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parse :: String -> [(Int, Int, Int)]
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parse = map toTuple . lines
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where
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toTuple :: String -> (Int, Int, Int)
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toTuple str = let [a, b, c] = splitOn 'x' str in (read a, read b, read c)
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toArea :: (Int, Int, Int) -> Int
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toArea (l, w, h) =
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let a = l * w
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b = w * h
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c = h * l
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in 2 * a + 2 * b + 2 * c + min a (min b c)
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solveA :: [(Int, Int, Int)] -> Int
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solveA = sum . map toArea
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-- >>> map toArea $ parse "2x3x4"
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-- [64]
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solveB = undefined
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