import Control.Applicative
import Data.List

delMax = \x -> delete (maximum x) x
delMin = \x -> delete (minimum x) x
average xs = fromIntegral(sum xs) / n
	where n = fromIntegral $ length xs

main = do
	s <-  delMin . delMax . map (read::String->Int) . words <$> getLine
	
	print $ average s