import java.util.Scanner;

public class Main {

	public static void main(String[] args) {
		Scanner scan = new Scanner(System.in);
		for (int i = 1; i > 0; i++){
		int x = scan.nextInt(); //????????§???????????\???
		int y = scan.nextInt(); //????????§???????????\???
		if(x == 0 && y == 0){
			break;
		}
		if(x > y){
			System.out.println(y + " " + x);
		} else{
			System.out.println(x + " " + y);
		}
		}
	}
}
/tmp/hf-datasets-cache/medium/datasets/42704881117311-config-parquet-and-info-qiankunmu-Project_CodeNet-896c9d36/hub/datasets--qiankunmu--Project_CodeNet_Python800_and_Java250/snapshots/c899fde44a77ba1cc14973ed3de064e4ff3aadc7/Project_CodeNet_Java250.tar.gz