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: Accepted)

using System;
using System.Collections.Generic;
//using System.Linq;
//using System.Text;
//using System.Threading.Tasks;

//namespace _3_C
//{
class Program
{
    static void Main(string[] args)
    {
        int i = 1;
        while (true)
        {

            //?????????????????????
            string readData = Console.ReadLine();

            // ???????????£????????????????????????????????¨??§????????????
            string[] readDataValue = readData.Split(' ');
            int x = int.Parse(readDataValue[0]);
            int y = int.Parse(readDataValue[1]);

            //x???0?????¨???????????????
            if (x == 0 && y == 0) break;

            //x???y??\????????¨???
            if (x <= y)
            {
                Console.WriteLine(x + " " + y );
            }
            else
            {
                Console.WriteLine(y + " " + x);
            }
            
            ++i;
        }
    }
}
//}