Partial progress on day 20

[advent-of-code-18.git] / src / advent20 / advent20.hs

diff --git a/src/advent20/advent20.hs b/src/advent20/advent20.hs
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+{-# LANGUAGE NegativeLiterals #-}
+{-# LANGUAGE OverloadedStrings #-}
+
+
+-- import Debug.Trace
+
+-- import Prelude hiding ((++))
+import Data.Text (Text)
+import qualified Data.Text as T
+import qualified Data.Text.IO as TIO
+
+import Data.Void (Void)
+import Text.Megaparsec hiding (State)
+import Text.Megaparsec.Char
+import qualified Text.Megaparsec.Char.Lexer as L
+import qualified Control.Applicative as CA
+
+import qualified Data.Map.Strict as M
+import Data.Map.Strict ((!))
+import qualified Data.Set as S
+
+import Linear (V2(..))
+
+import Control.Monad.State.Lazy
+
+type Coord = V2 Integer -- x, y, with north and east incresing values (origin a bottom left)
+data Door = Door Coord Coord deriving (Show, Eq, Ord)
+type Doors = S.Set Door
+
+makeDoor :: Coord -> Coord -> Door
+makeDoor a b 
+    | a < b = Door a b
+    | otherwise = Door b a
+
+
+
+
+main :: IO ()
+main = do 
+        text <- TIO.readFile "data/advent20.txt"
+        print $ T.length text
+        -- let (ip, instrs) = successfulParse text
+        -- print (ip, instrs)
+        -- -- print $ part1 ip instrs
+        -- print $ sum [i | i <- [1..1032], 1032 `mod` i == 0]
+        -- -- print $ part2 ip instrs
+        -- print $ sum [i | i <- [1..10551432], 10551432 `mod` i == 0]
+
+
+
+-- type Parser = Parsec Void Text
+type Parser = ParsecT Void Text (StateT [Coord] [])
+
+
+sc :: Parser ()
+sc = L.space (skipSome spaceChar) CA.empty CA.empty
+
+lexeme  = L.lexeme sc
+-- integer = lexeme L.decimal
+symb = L.symbol sc
+branchSepP = symb "|"
+openBranchP = symb "("
+closeBranchP = symb ")"
+startP = symb "^"
+endP = symb "$"
+
+doorP :: Parser Coord
+doorP = nP <|> sP <|> eP <|> wP
+nP = (symb "N" *> pure (V2  0  1))
+sP = (symb "S" *> pure (V2  0 -1))
+eP = (symb "E" *> pure (V2  1  0))
+wP = (symb "W" *> pure (V2 -1  0))
+
+-- instructionFileP = (startP `between` endP) branchesP
+
+-- branchesP :: MyParser Doors
+-- branchesP = fmap S.unions . many $ choiceP <|> pathP
+
+-- choiceP :: MyParser Doors
+-- choiceP = (openBranchP `between` closeBranchP)  $ do
+--     here <- get
+--     return fmap S.unions (`sepBy` branchSepP) $ do
+--         put here
+--         return branchesP
+
+
+
+-- pathP :: MyParser Doors
+-- pathP = S.fromList <$> many stepP
+pathP = many stepP
+
+-- stepP :: MyParser Door
+stepP = do
+    heres <- get
+    delta <- doorP
+    let theres = map (+delta) heres 
+    put theres
+    return (map (\h -> makeDoor h (h + delta)) heres)
+
+-- choiceP :: MyParser [Door]
+-- choiceP = (openBranchP `between` closeBranchP) $ do
+--     heres <- get
+--     do 
+--         here <- heres
+--         put [here]
+--         branch <- (pathP `sepBy` branchSepP)
+--         return branch
+
+    -- fmap concat $ (`sepBy` branchSepP) $ do
+    --     here <- heres 
+    --     pathP
+
+
+{-    heres <- get
+    choices <- (`sepBy` branchSepP) $ do
+        put heres
+        pathP
+    return $ concat choices -- (S.unions choices)-}
+
+-- choiceOrPathP = many (choiceP <|> pathP)
+
+
+-- successfulParse :: Text -> (Integer, [Instruction])
+-- successfulParse input = 
+--         case parse instructionsP "input" input of
+--                 Left  _error -> (0, []) -- TIO.putStr $ T.pack $ parseErrorPretty err
+--                 Right instructions  -> instructions
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