import java.util.*;

public class Main {
	public static void main(String[] arg){
		Scanner in = new Scanner(System.in);
		while(in.hasNext()) {
            String buf = in.nextLine();
            if(buf.equals("0 0")){
            	break;
			}
            String[] num = buf.split(" ");
            if(Integer.parseInt(num[0]) < Integer.parseInt(num[1])){
            	System.out.println(num[0]+" "+num[1]);
            }else{
            	System.out.println(num[1]+" "+num[0]);
            }
        }
	}
}
/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