data Hand = Rock | Paper | Scissor deriving (Eq,Enum,Bounded,Show)
instance Ord Hand where
    compare x y = case (fromEnum x - fromEnum y) `mod` 3 of
                    0 -> EQ
                    1 -> GT
                    _ -> LT

(+.) :: Hand -> Int -> Hand
(+.) a b = toEnum $ flip mod 3 $ (+) (fromEnum a) b


main :: IO ()
main = do
  input <- map (concat . words) . lines <$> readFile "input"
  print $ day2 id input
  print $ day2 realStrat input

toHands :: [Char] -> [Hand]
toHands x = map toEnum $ (zipWith subtract [65,88]) (map fromEnum x)

realStrat :: [Hand] -> [Hand]
realStrat (a:b:[]) = [a,a +. fromEnum (b +. 2)]

day2 :: ([Hand] -> [Hand]) -> [[Char]] -> Int
day2 f = sum . map (play . f . toHands)

play :: [Hand] -> Int
play (x:y:[]) = fromEnum y + 1 + if x == y then 3 else fromEnum (x<y) * 6