import Control.Applicative

max3 :: Int -> Int -> Int -> Int
max3 a b c = max (max a b) c

solve :: Int -> Int -> Int
solve a b = max3 add sub mul
    where add = a + b
          sub = a - b
          mul = a * b


main :: IO ()
main = do
    [a, b] <- map read . words <$> getLine
    putStrLn $ show (solve a b)