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 iNum1 = scan.nextInt();
                        int iNum2 = scan.nextInt();
                        if(iNum1 == 0 && iNum2 == 0)
                                break;
                        if(iNum1 > iNum2){
                        	int temp = iNum1;
                        	iNum1 = iNum2;
                        	iNum2 = temp;
                        }
                        System.out.println(iNum1 + " " + iNum2);
                }
	}
}
/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