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import Text.Parsec.String (Parser)
import Text.Parsec
import System.Environment
import Data.List
import Data.Function
import Data.Maybe
import qualified Data.Map as M
import Control.Monad
data Color = Red | Green | Blue deriving (Show,Eq,Ord)
type Handful = (Color, Int)
type Set = M.Map Color Int
type Game = (Int, [Set])
red = try $ string "red" *> pure Red
green = try $ string "green" *> pure Green
blue = try $ string "blue" *> pure Blue
color :: Parser Color
color = red <|> green <|> blue
handful :: Parser Handful
handful = space *> (flip (,) <$> read <$> many1 digit) <* space <*> color
set = M.fromList <$> (sepBy handful $ string ",")
game = string "Game " *> ((,) <$> read <$> many1 digit) <* string ":" <*> sepBy set (string ";")
games = sepBy game newline
solution :: Game -> Maybe Int
solution (i,m) = do
let m' = M.unionsWith max m
guard $ M.findWithDefault 0 Red m' <= 12
guard $ M.findWithDefault 0 Green m' <= 13
guard $ M.findWithDefault 0 Blue m' <= 14
return i
main = head <$> getArgs >>= readFile >>= print . sum . catMaybes . map solution . either (error.show) id . parse games ""
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