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+module Day22B where
+
+import System.Environment (getArgs)
+import Text.Printf
+import Data.List.Split (splitOn)
+
+-- Types
+
+data Player = P1 | P2;
+
+-- Top = First
+type Deck = [Int];
+
+-- (P1, P2)
+type State = (Deck, Deck);
+
+-- Parsing
+
+parseDeck :: String -> Deck
+parseDeck = map read . tail . lines
+
+-- Parse the input
+parseInput :: String -> State
+parseInput xs = (p1, p2)
+      where [p1, p2] = map parseDeck $ splitOn "\n\n" xs
+
+-- Parse a file given the path
+-- Returns list of instructions
+parseFromFile :: String -> IO State
+parseFromFile s = do 
+                   contents <- readFile s;
+                   return $ parseInput contents;
+
+takeTurn :: State -> [State] -> (State, [State])
+takeTurn s@(c1:p1, c2:p2) h | s `elem` h = ((p1 ++ p2 ++ [c1, c2], []), h)
+                            | length p1 >= c1
+                              && length p2 >= c2 = case getPlayerWinner ((take c1 p1, take c2 p2), []) of 
+                                                     P1 -> p1Win
+                                                     P2 -> p2Win
+                            | c1 > c2 = p1Win
+                            | otherwise = p2Win
+                where p1Win = ((p1 ++ [c1, c2], p2), h')
+                      p2Win = ((p1, p2 ++ [c2, c1]), h')
+                      h' = s : h
+
+takeTurn ([], _) _ = error "game is over!"
+takeTurn (_, []) _ = error "game is over!"
+
+getPlayerWinner :: (State, [State]) -> Player
+getPlayerWinner ((_, []), _) = P1
+getPlayerWinner (([], _), _) = P2
+getPlayerWinner (s, h) = getPlayerWinner $ takeTurn s h
+
+getWinner :: (State, [State]) -> Deck
+getWinner ((p1, []), _) = p1
+getWinner (([], p2), _) = p2
+getWinner (s, h) = getWinner $ takeTurn s h
+
+getScore :: Deck -> Int
+getScore d = sum $ zipWith (*) (reverse [1..length d]) d
+
+-- runghc --ghc-arg='-package split' 22a.hs inputs/day22
+main :: IO ()
+main = do 
+        args <- getArgs;
+        s <- parseFromFile (head args);
+
+        let winnerScore = getScore $ getWinner (s, []);
+        printf "Answer = %d\n" winnerScore :: IO ();
+
+        return ();