33 lines
934 B
Haskell
33 lines
934 B
Haskell
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#!/usr/bin/env runghc
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module Day7.Part1 where
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import Day7
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import Data.Array
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import Data.Graph
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import Data.Maybe
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main = interact (show . solve "shiny gold" . parse rules)
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-- solve myBag rs = (+) (-1) $ forestSize $ dfs graph [vertex]
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-- solve myBag rs = length $ keys -- filter (path graph vertex . fromJust . vertexFromKey) keys
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solve myBag rs = graph
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where keys = filter (/= myBag) $ map ruleToKey rs
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(graph, keyFromVertex, vertexFromKey) = graphFromEdges . map ruleToEdge $ rs
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Just vertex = vertexFromKey myBag
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ruleToKey = name . container
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forestSize [] = 0
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forestSize ((Node _ branches):siblings) = nodeSum + siblingSum + branchSum
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where
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nodeSum = 1
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siblingSum = forestSize siblings
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branchSum = forestSize branches
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ruleToEdge :: Rule -> (String, String, [String])
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ruleToEdge r = (node, node, edges)
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where
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node = name . container $ r
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edges = map (name . item) . contents $ r
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