import Data.List(sort)

main :: IO ()
main = myPrint . map (sort . map read . words) . lines =<< getContents

myPrint :: [[Int]] -> IO ()
myPrint [[0, 0]] = return ()
myPrint [] = return ()
myPrint (x:xs) = do
    putStrLn . unwords . map show $ x
    myPrint xs