{"header":{"message":"Day 8 solution","description":null,"timestamp":"2021-01-14T00:58:34Z","authors":[{"email":"jeremy.list@youdo.co.nz","name":"Jeremy List"}]},"hash":"W7FIR7DH7GKAPUIL535JFW2XRP7UADFJHTFQAKPBRLPJZFBEJWPAC","authors":[],"deps":{"hashes":[["W7FIR7DH7GKAPUIL535JFW2XRP7UADFJHTFQAKPBRLPJZFBEJWPAC","Day 8 solution"],["AA",null],["B527MN663VOX7PY6BCLAAU62WDPTI4JTVLNUP2UR74S4KJYKT4HQC","Solve day 1 for 2020"]],"deps":["B527MN663VOX7PY6BCLAAU62WDPTI4JTVLNUP2UR74S4KJYKT4HQC"],"known":[]},"hunks":[{"FileAdd":{"meta":{"basename":"day8.hs","metadata":0},"context":[{"change":2,"pos":17}],"contents":[{"Add":"{-# LANGUAGE LambdaCase #-}"},{"Add":"import Control.Applicative"},{"Add":"import Control.Monad.State"},{"Add":"import Data.Char"},{"Add":"import Data.Either"},{"Add":"import Data.Maybe"},{"Add":"import Data.List (intercalate)"},{"Add":"import Data.Monoid"},{"Add":"import qualified Data.IntMap as IM"},{"Add":"import qualified Data.Set as S"},{"Add":"import System.Environment"},{"Add":""},{"Add":"data Operation = ACC | JMP | NOP deriving (Eq,Show)"},{"Add":""},{"Add":"pcIncrement :: Operation -> Int -> Int"},{"Add":"pcIncrement JMP i = i"},{"Add":"pcIncrement _ _ = 1"},{"Add":""},{"Add":"accIncrement :: Operation -> Int -> Int"},{"Add":"accIncrement ACC i = i"},{"Add":"accIncrement _ _ = 0"},{"Add":""},{"Add":"runBoot :: IM.IntMap (Operation,Int) -> [(Int,Int)]"},{"Add":"runBoot b = case IM.lookupMin b of"},{"Add":" Nothing -> []"},{"Add":" Just (pc0,_) -> go pc0 0"},{"Add":" where"},{"Add":" go pc acc = case IM.lookup pc b of"},{"Add":" Nothing -> []"},{"Add":" Just (op,i) -> let"},{"Add":" pc' = pc + pcIncrement op i"},{"Add":" acc' = acc + accIncrement op i"},{"Add":" in (pc', acc') : go pc' acc'"},{"Add":""},{"Add":"repairAttempts :: Alternative f =>"},{"Add":" IM.IntMap (Operation, Int) -> f (IM.IntMap (Operation, Int))"},{"Add":"repairAttempts = alterEach $ \\(opc,i) -> case opc of"},{"Add":" ACC -> empty"},{"Add":" NOP -> pure $ Just (JMP,i)"},{"Add":" JMP -> pure $ Just (NOP,i)"},{"Add":""},{"Add":"alterEach :: Alternative f =>"},{"Add":" (a -> f (Maybe a)) -> IM.IntMap a -> f (IM.IntMap a)"},{"Add":"alterEach f m = getAlt $"},{"Add":" IM.foldMapWithKey (\\k _ -> Alt $ IM.alterF (f . fromJust) k m) m"},{"Add":""},{"Add":"accBeforeLoop :: [(Int,Int)] -> Maybe Int"},{"Add":"accBeforeLoop = go (S.singleton 0) . ((0,0):) where"},{"Add":" go v ((_,acc):r@((pc,_):_)) = either Just (flip go r) $ S.alterF (\\p -> if p then Left acc else Right True) pc v"},{"Add":" go _ _ = Nothing"},{"Add":""},{"Add":"accOnComplete :: Int -> [(Int,Int)] -> Maybe Int"},{"Add":"accOnComplete t = go S.empty where"},{"Add":" go _ [] = Nothing"},{"Add":" go _ [(pc,acc)]"},{"Add":" | pc == t = Just acc"},{"Add":" | otherwise = Nothing"},{"Add":" go v ((pc,acc):r)"},{"Add":" | pc `S.member` v = Nothing"},{"Add":" | otherwise = go (S.insert pc v) r"},{"Add":""},{"Add":"anyChar :: StateT String [] Char"},{"Add":"anyChar = StateT (\\case"},{"Add":" [] -> []"},{"Add":" (a:r) -> [(a,r)]"},{"Add":" )"},{"Add":""},{"Add":"string :: String -> StateT String [] ()"},{"Add":"string [] = return ()"},{"Add":"string (a:r) = anyChar >>= \\c -> if a == c"},{"Add":" then string r"},{"Add":" else empty"},{"Add":""},{"Add":"opcode :: StateT String [] Operation"},{"Add":"opcode = (ACC <$ string \"acc\") <|>"},{"Add":" (JMP <$ string \"jmp\") <|>"},{"Add":" (NOP <$ string \"nop\")"},{"Add":""},{"Add":"natural :: Num a => StateT String [] a"},{"Add":"natural = go 0 where"},{"Add":" go acc = anyChar >>= \\c -> if isDigit c"},{"Add":" then let"},{"Add":" acc' = acc * 10 + fromIntegral (digitToInt c)"},{"Add":" in acc' `seq` return acc' <|> go acc'"},{"Add":" else empty"},{"Add":""},{"Add":"eos :: StateT String [] ()"},{"Add":"eos = StateT (\\case"},{"Add":" [] -> [((),[])]"},{"Add":" _ -> []"},{"Add":" )"},{"Add":""},{"Add":"neos :: StateT String [] ()"},{"Add":"neos = StateT (\\case"},{"Add":" [] -> []"},{"Add":" _ -> [((),[])]"},{"Add":" )"},{"Add":""},{"Add":"line :: StateT String [] (Operation,Int)"},{"Add":"line = (,) <$>"},{"Add":" (opcode <* string \" \") <*>"},{"Add":" ("},{"Add":" ((id <$ string \"+\") <|> (negate <$ string \"-\")) <*>"},{"Add":" natural"},{"Add":" )"},{"Add":""},{"Add":"sepBy :: Alternative m => m a -> m s -> m [a]"},{"Add":"sepBy a s = pure [] <|>"},{"Add":" ((:) <$> a <*> many (s *> a))"},{"Add":""},{"Add":"file :: StateT String [] (IM.IntMap (Operation,Int))"},{"Add":"file = (IM.fromList . zip [0..]) <$> sepBy line (string \"\\n\") <* (pure () <|> void (string \"\\n\"))"},{"Add":""},{"Add":"main = do"},{"Add":" (part:fn:_) <- getArgs"},{"Add":" (b:_) <- evalStateT (file <* eos) <$> readFile fn"},{"Add":" print $ case part of"},{"Add":" \"1\" -> fromJust $ accBeforeLoop $ runBoot b"},{"Add":" \"2\" -> let"},{"Add":" gc = accOnComplete $ IM.size b"},{"Add":" in head $ do"},{"Add":" b' <- repairAttempts b"},{"Add":" maybeToList $ gc $ runBoot b'"},{"Add":""},{"Add":"showOps :: IM.IntMap (Operation,Int) -> String"},{"Add":"showOps = intercalate \"\\n\" . map (\\(op,i) ->"},{"Add":" map toLower (show op) ++"},{"Add":" \" \" ++"},{"Add":" (if i < 0 then \"-\" else \"+\") ++"},{"Add":" show (abs i)"},{"Add":" ) . IM.elems"}]}}],"owner":"quickdudley","repo":"adventofcode","token":"v6DCoPUJycdDL6WedtBRV1v2DM1SCEmGIffQv2P7kUo=","login":null}

…

Dependencies

Change contents