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import Prelude
import Text.Parsec.String (Parser)
import Text.Parsec
import System.Environment
import Control.Monad
import qualified Data.Set as S
type Card = (Int, S.Set Int, S.Set Int)
numbers = S.fromList <$> ((many1 space) *> sepEndBy (read <$> many1 digit) (many1 space))
card :: Parser Card
card = (,,) <$> (string "Card" *> spaces *> (read <$> many1 digit) <* char ':') <*> numbers <* (char '|') <*> numbers
cards = many1 card
solution :: [Card] -> Int
solution xs = sum $ map f xs where
f (id,picked,winning) = case (length $ S.intersection picked winning) of
0 -> 0
n -> 2 ^ (pred n)
main = liftM2 (>>=) readFile (((print . solution . either (error.show) id) .) . parse cards) =<< head <$> getArgs
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