22 lines
515 B
Haskell
22 lines
515 B
Haskell
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#!/usr/bin/env runghc
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module Day8.Part2 where
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import Data.Array
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import Data.List (find)
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import Data.Maybe (fromJust)
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import Day8
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main = interact (show . acc . fromJust . find (not . looped) . map run . flips . parse program)
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flips :: Program -> [Program]
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flips pgrm = (pgrm:(flips' pgrm 0))
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flips' pgrm ix
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| outOfBounds pgrm ix = []
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| otherwise = (pgrm // [(ix, flipped)]):(flips' pgrm (ix + 1))
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where
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flipped = case (pgrm ! ix) of
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(Nop a) -> Jmp a
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(Jmp a) -> Nop a
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x -> x
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