Soctopus Prediction

Soctopus.hs

-- | <http://ncss.edu.au/challenge/ncss_challenge_2012.pdf>

class Semigroup a where
    (<>) :: a -> a -> a

data Result = Team String | Draw Int

resultLength :: Result -> Int
resultLength (Team name) = length name
resultLength (Draw lgth) = lgth

instance Semigroup Result where
    a <> b
      | x < y = b
      | x > y = a
      | otherwise = Draw x
      where
        x = resultLength a
        y = resultLength b

showResult :: Result -> String
showResult (Team name) = name
showResult (Draw _) = "Draw"