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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
import Data.Maybe
type Card = (S.Set Int, S.Set Int)
numbers = S.fromList <$> ((many1 space) *> sepEndBy (read <$> many1 digit) (many1 space))
card :: Parser Card
card = string "Card" *> spaces *> many1 digit *> char ':' *> liftM2 (,) (numbers <* (char '|')) numbers
cards = many1 card
solution :: [Card] -> Int
solution = sum . map (+1) . foldr f [] where
f (picked,winning) ws = w : ws where
m = length $ S.intersection picked winning
w = m + sum (take m ws)
main = liftM2 (>>=) readFile (((print . solution . either (error.show) id) .) . parse cards) =<< head <$> getArgs
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