import Data.List
import Control.Lens
import Control.Arrow

main :: IO ()
main = do
  input <- lines <$> readFile "input"
  let counts = map ((\[x,y]->x>y) . map length . group . sort) $ transpose input
  let (gamma,epsilon) = boolToDec *** boolToDec $ (id &&& map not) counts
  print $ gamma * epsilon

boolToDec :: [Bool] -> Int
boolToDec = sum . imap (\x y->(2^x)*y) . reverse . map fromEnum