Thành phố Cuồng loạn

Monad increase n = Just (n + 1) addOne n = [n + 1] main = do print $ Nothing >> (Just 0) -- Nothing print $ (Just 0) >> (Nothing :: Maybe Int) -- Nothing print $ (Just 0) >> Nothing >> (Just 1) -- Nothing print $ (Just 0) >> (Just 1) >> (Just 2) -- Jus ...