public class Main{
  public void run(java.io.InputStream in, java.io.PrintStream out){
    java.util.Scanner sc = new java.util.Scanner(in);
/*answer*/
    int a, b, tmp;
    for(;;){
      a = sc.nextInt();
      b = sc.nextInt();
      if(b < a){
        tmp = a;
        a = b;
        b = tmp;
      }

      if(b != 0){
        System.out.println(a + " " + b);
      }else{
        break;
      }
    }  

/*fin*/
    sc.close();
  }
  public static void main(String[] args){
    (new Main()).run(System.in, System.out);
  }
} public class Main{
  public void run(java.io.InputStream in, java.io.PrintStream out){
    java.util.Scanner sc = new java.util.Scanner(in);
/*answer*/
    int a, b, tmp;
    for(;;){
      a = sc.nextInt();
      b = sc.nextInt();
      if(b < a){
        tmp = a;
        a = b;
        b = tmp;
      }

      if(b != 0){
        System.out.println(a + " " + b);
      }else{
        break;
      }
    }  

/*fin*/
    sc.close();
  }
  public static void main(String[] args){
    (new Main()).run(System.in, System.out);
  }
} Main public void run(java.io.InputStream in, java.io.PrintStream out){
    java.util.Scanner sc = new java.util.Scanner(in);
/*answer*/
    int a, b, tmp;
    for(;;){
      a = sc.nextInt();
      b = sc.nextInt();
      if(b < a){
        tmp = a;
        a = b;
        b = tmp;
      }

      if(b != 0){
        System.out.println(a + " " + b);
      }else{
        break;
      }
    }  

/*fin*/
    sc.close();
  } run {
    java.util.Scanner sc = new java.util.Scanner(in);
/*answer*/
    int a, b, tmp;
    for(;;){
      a = sc.nextInt();
      b = sc.nextInt();
      if(b < a){
        tmp = a;
        a = b;
        b = tmp;
      }

      if(b != 0){
        System.out.println(a + " " + b);
      }else{
        break;
      }
    }  

/*fin*/
    sc.close();
  } java.util.Scanner sc = new java.util.Scanner(in); sc new java.util.Scanner(in) int a a b b tmp; tmp for(;;){
      a = sc.nextInt();
      b = sc.nextInt();
      if(b < a){
        tmp = a;
        a = b;
        b = tmp;
      }

      if(b != 0){
        System.out.println(a + " " + b);
      }else{
        break;
      }
    } ; {
      a = sc.nextInt();
      b = sc.nextInt();
      if(b < a){
        tmp = a;
        a = b;
        b = tmp;
      }

      if(b != 0){
        System.out.println(a + " " + b);
      }else{
        break;
      }
    } {
      a = sc.nextInt();
      b = sc.nextInt();
      if(b < a){
        tmp = a;
        a = b;
        b = tmp;
      }

      if(b != 0){
        System.out.println(a + " " + b);
      }else{
        break;
      }
    } a = sc.nextInt() a sc.nextInt() sc.nextInt sc b = sc.nextInt() b sc.nextInt() sc.nextInt sc if(b < a){
        tmp = a;
        a = b;
        b = tmp;
      } b < a b a {
        tmp = a;
        a = b;
        b = tmp;
      } tmp = a tmp a a = b a b b = tmp b tmp if(b != 0){
        System.out.println(a + " " + b);
      }else{
        break;
      } b != 0 b 0 {
        System.out.println(a + " " + b);
      } System.out.println(a + " " + b) System.out.println System.out System System.out a + " " + b a + " " + b a " " b {
        break;
      } break; sc.close() sc.close sc java.io.InputStream in in java.io.PrintStream out out public static void main(String[] args){
    (new Main()).run(System.in, System.out);
  } main {
    (new Main()).run(System.in, System.out);
  } (new Main()).run(System.in, System.out) (new Main()).run (new Main()) System.in System System.in System.out System System.out String[] args args public class Main{
  public void run(java.io.InputStream in, java.io.PrintStream out){
    java.util.Scanner sc = new java.util.Scanner(in);
/*answer*/
    int a, b, tmp;
    for(;;){
      a = sc.nextInt();
      b = sc.nextInt();
      if(b < a){
        tmp = a;
        a = b;
        b = tmp;
      }

      if(b != 0){
        System.out.println(a + " " + b);
      }else{
        break;
      }
    }  

/*fin*/
    sc.close();
  }
  public static void main(String[] args){
    (new Main()).run(System.in, System.out);
  }
} public class Main{
  public void run(java.io.InputStream in, java.io.PrintStream out){
    java.util.Scanner sc = new java.util.Scanner(in);
/*answer*/
    int a, b, tmp;
    for(;;){
      a = sc.nextInt();
      b = sc.nextInt();
      if(b < a){
        tmp = a;
        a = b;
        b = tmp;
      }

      if(b != 0){
        System.out.println(a + " " + b);
      }else{
        break;
      }
    }  

/*fin*/
    sc.close();
  }
  public static void main(String[] args){
    (new Main()).run(System.in, System.out);
  }
} Main
public class Main{
  public void run(java.io.InputStream in, java.io.PrintStream out){
    java.util.Scanner sc = new java.util.Scanner(in);
/*answer*/
    int a, b, tmp;
    for(;;){
      a = sc.nextInt();
      b = sc.nextInt();
      if(b < a){
        tmp = a;
        a = b;
        b = tmp;
      }

      if(b != 0){
        System.out.println(a + " " + b);
      }else{
        break;
      }
    }  

/*fin*/
    sc.close();
  }
  public static void main(String[] args){
    (new Main()).run(System.in, System.out);
  }
}