
import java.util.Scanner;

public class Main {
	public static void main(String args[]) {
		Scanner sc = new Scanner(System.in);
		int x, y;
		while(true) {
			x = sc.nextInt();
			y = sc.nextInt();
			if(x > y) {
				System.out.println(+y + " " + x);
			}
			if(x == 0 && y == 0) {
				break;

			}

			if(x < y) {
				System.out.println(+x + " " + y);
			}
			if(x == y) {
				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