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;

namespace ITP1_3_C
{
	class Program
	{
		static void Main(string[] args)
		{
			List<Tuple<int, int>> ts = new List<Tuple<int, int>>();

			for(int i = 1; i <= 3000; i++) {
				string[] vs = Console.ReadLine().Split(' ');
				int x = int.Parse(vs[0]);
				int y = int.Parse(vs[1]);

				if(x == 0 && y == 0) {
					break;
				}

				ts.Add(Tuple.Create(x, y));
			}

			foreach(Tuple<int, int> t in ts) {
				if(t.Item1 < t.Item2) {
					Console.WriteLine($"{t.Item1} {t.Item2}");
				}
				else {
					Console.WriteLine($"{t.Item2} {t.Item1}");
				}
			}
		}
	}
}