module Main where

import qualified Data.Vector as Vector
import Data.List

main :: IO ()
main =
    print =<< solve <$> getInt


getInt :: IO [Integer]
getInt = map read <$> words <$> getLine

solve :: [Integer] -> Integer
solve [h, w] = (div (h + 1) 2) * (div (w + 1) 2) + (div h 2) * (div w 2)
