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;
using System.Collections.Generic;

namespace JKTX_AOJ2015
{
    public class Data
    {
        public int A { get; set; }
        public int B { get; set; }
    }

    class Program
    {
        static void Main(string[] args)
        {
            var dataList = new List<Data>();

            while (true)
            {
                string[] str = Console.ReadLine().Split(' ');
                Data data = new Data();
                data.A = int.Parse(str[0]);
                data.B = int.Parse(str[1]);

                if (data.A == 0 && data.B == 0)
                {
                    break;
                }

                dataList.Add(data);
            }

            foreach (var item in dataList)
            {
                if (item.A < item.B)
                {
                    Console.WriteLine("{0} {1}", item.A, item.B);
                }
                else
                {
                    Console.WriteLine("{0} {1}", item.B, item.A);
                }
            }
        }
    }
}