31 lines
680 B
Haskell
31 lines
680 B
Haskell
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module Day3.Part1 (
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splitContents,
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itemsInBoth,
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itemPriority,
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priority,
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rearrangementPriority,
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)
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where
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import qualified Data.Set as Set
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import Day3.Shared
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splitContents :: Contents -> (Contents, Contents)
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splitContents c = splitAt middle c
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where
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middle = length c `div` 2
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itemsInBoth :: Contents -> Contents
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itemsInBoth cs = Set.toList $ leftSet `Set.intersection` rightSet
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where
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(left, right) = splitContents cs
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leftSet = Set.fromList left
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rightSet = Set.fromList right
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rearrangementPriority :: String -> Int
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rearrangementPriority input = sum priorities
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where
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contents = lines input
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priorities = map (priority . itemsInBoth) contents
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