import Control.Applicative ((<$>))
import Data.List (sort)


computeSum :: Integral a => [a] -> a
computeSum ps = (head qs `div` 2) + sum (tail qs)
    where qs = reverse $ sort ps


main :: IO ()
main = do
    ps <- tail . fmap read . lines <$> getContents :: IO [Int]
    print $ computeSum ps