import java.util.Scanner;

class Main{
    public static void main(String[] args) throws Exception{

        Scanner sc = new Scanner(System.in);

        while(sc.hasNext()){

            int x = sc.nextInt();
            int y = sc.nextInt();

            if(x == 0 && y == 0){
                break;
            }
            if(x < y){
                System.out.println(x + " " + y);
            }else {
                System.out.println(y + " " + x);
            }
        }

    }
} import java.util.Scanner; Scanner java.util class Main{
    public static void main(String[] args) throws Exception{

        Scanner sc = new Scanner(System.in);

        while(sc.hasNext()){

            int x = sc.nextInt();
            int y = sc.nextInt();

            if(x == 0 && y == 0){
                break;
            }
            if(x < y){
                System.out.println(x + " " + y);
            }else {
                System.out.println(y + " " + x);
            }
        }

    }
} Main public static void main(String[] args) throws Exception{

        Scanner sc = new Scanner(System.in);

        while(sc.hasNext()){

            int x = sc.nextInt();
            int y = sc.nextInt();

            if(x == 0 && y == 0){
                break;
            }
            if(x < y){
                System.out.println(x + " " + y);
            }else {
                System.out.println(y + " " + x);
            }
        }

    } main {

        Scanner sc = new Scanner(System.in);

        while(sc.hasNext()){

            int x = sc.nextInt();
            int y = sc.nextInt();

            if(x == 0 && y == 0){
                break;
            }
            if(x < y){
                System.out.println(x + " " + y);
            }else {
                System.out.println(y + " " + x);
            }
        }

    } Scanner sc = new Scanner(System.in); sc new Scanner(System.in) while(sc.hasNext()){

            int x = sc.nextInt();
            int y = sc.nextInt();

            if(x == 0 && y == 0){
                break;
            }
            if(x < y){
                System.out.println(x + " " + y);
            }else {
                System.out.println(y + " " + x);
            }
        } sc.hasNext() sc.hasNext sc {

            int x = sc.nextInt();
            int y = sc.nextInt();

            if(x == 0 && y == 0){
                break;
            }
            if(x < y){
                System.out.println(x + " " + y);
            }else {
                System.out.println(y + " " + x);
            }
        } int x = sc.nextInt(); x sc.nextInt() sc.nextInt sc int y = sc.nextInt(); y sc.nextInt() sc.nextInt sc if(x == 0 && y == 0){
                break;
            } x == 0 && y == 0 x == 0 x 0 y == 0 y 0 {
                break;
            } break; if(x < y){
                System.out.println(x + " " + y);
            }else {
                System.out.println(y + " " + x);
            } x < y x y {
                System.out.println(x + " " + y);
            } System.out.println(x + " " + y) System.out.println System.out System System.out x + " " + y x + " " + y x " " y {
                System.out.println(y + " " + x);
            } System.out.println(y + " " + x) System.out.println System.out System System.out y + " " + x y + " " + x y " " x String[] args args
import java.util.Scanner;

class Main{
    public static void main(String[] args) throws Exception{

        Scanner sc = new Scanner(System.in);

        while(sc.hasNext()){

            int x = sc.nextInt();
            int y = sc.nextInt();

            if(x == 0 && y == 0){
                break;
            }
            if(x < y){
                System.out.println(x + " " + y);
            }else {
                System.out.println(y + " " + x);
            }
        }

    }
}