import java.awt.*;
import java.awt.geom.*;
import java.io.*;

import java.util.*;
class Main {


	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		while(true) {
			int a = sc.nextInt();
			int b = sc.nextInt();
			if(a == 0 && b == 0) break;
			
			System.out.println((a < b)?(a + " " + b):(b + " " + a));
		}
	}
} import java.awt.*; awt.* java import java.awt.geom.*; geom.* java.awt import java.io.*; io.* java import java.util.*; util.* java class Main {


	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		while(true) {
			int a = sc.nextInt();
			int b = sc.nextInt();
			if(a == 0 && b == 0) break;
			
			System.out.println((a < b)?(a + " " + b):(b + " " + a));
		}
	}
} Main public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		while(true) {
			int a = sc.nextInt();
			int b = sc.nextInt();
			if(a == 0 && b == 0) break;
			
			System.out.println((a < b)?(a + " " + b):(b + " " + a));
		}
	} main {
		Scanner sc = new Scanner(System.in);
		while(true) {
			int a = sc.nextInt();
			int b = sc.nextInt();
			if(a == 0 && b == 0) break;
			
			System.out.println((a < b)?(a + " " + b):(b + " " + a));
		}
	} Scanner sc = new Scanner(System.in); sc new Scanner(System.in) while(true) {
			int a = sc.nextInt();
			int b = sc.nextInt();
			if(a == 0 && b == 0) break;
			
			System.out.println((a < b)?(a + " " + b):(b + " " + a));
		} true {
			int a = sc.nextInt();
			int b = sc.nextInt();
			if(a == 0 && b == 0) break;
			
			System.out.println((a < b)?(a + " " + b):(b + " " + a));
		} int a = sc.nextInt(); a sc.nextInt() sc.nextInt sc int b = sc.nextInt(); b sc.nextInt() sc.nextInt sc if(a == 0 && b == 0) break; a == 0 && b == 0 a == 0 a 0 b == 0 b 0 break; System.out.println((a < b)?(a + " " + b):(b + " " + a)) System.out.println System.out System System.out (a < b)?(a + " " + b):(b + " " + a) (a < b) a b (a + " " + b) a + " " + b a " " b (b + " " + a) b + " " + a b " " a String[] args args
import java.awt.*;
import java.awt.geom.*;
import java.io.*;

import java.util.*;
class Main {


	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		while(true) {
			int a = sc.nextInt();
			int b = sc.nextInt();
			if(a == 0 && b == 0) break;
			
			System.out.println((a < b)?(a + " " + b):(b + " " + a));
		}
	}
}