Problem:
Swapping Two Numbers

Write a program which reads two integers x and y, and prints them in ascending order.

Input

The input consists of multiple datasets. Each dataset consists of two integers x and y separated by a single space.

The input ends with two 0 (when both x and y are zero). Your program should not process for these terminal symbols.

Output

For each dataset, print x and y in ascending order in a line. Put a single space between x and y.

Constraints

0 ≤ x, y ≤ 10000

the number of datasets ≤ 3000

Sample Input

3 2
2 2
5 3
0 0

Sample Output

2 3
2 2
3 5

Solution in C# (judge verdict: Wrong Answer)

using System;
using System.Linq;

namespace _3_C
{
    class Program
    {
        static void Main(string[] args)
        { 
            bool z = true;

           while (z)
            {
                int[] x1 = Console.ReadLine().Split().Select(int.Parse).ToArray();

                if (!(x1[0]==0&&x1[1]==0))
                {
                    int[] x2 = new int[] { x1[0],x1[1] };
                    Array.Sort(x2);
                    Console.WriteLine(x1[0]+" "+x1[1]);
                }
                else
                {
                    z = false;
                }
            }
        }
    }
}