import Control.Applicative

sumPair :: [[Integer]] -> [Integer]
sumPair [] = []
sumPair (x:y:ys) = ((head x)+(head y)) : (sumPair ys)

main = do
  input <- (fmap (fmap (read :: String -> Integer) . words) . lines) <$> getContents
  mapM_ print $ sumPair $ tail input