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;

public class Program
{
	public static void Main(string[] args)
	{
		var ss = new StreamScanner();
		//---------------------------------
		//var x = ss.Next<int>();
		//var y = ss.Next<int>();
		for (int i = 1; i <= 3000; i++)
		{
			int x = ss.Next<int>();
			int y = ss.Next<int>();
			if (x == 0 && y == 0)
			{
				break;
			}
			else if (x <= y)
			{
				Console.WriteLine(x+" "+y);
			}
			else if(x>y)
			{
				Console.WriteLine(y+" "+x);
			}


		}




		/*
		//????????????int, double, string?????????????????£????????????
		int i = ss.Next<int>();
		double d = ss.Next<double>();
		string s = ss.Next<string>();

		//?????°???????????????????????¨?????????????????????????????????????????????????´???????
		int[] array = ss.Next<int>(10);
		*/
		//---------------------------------
	}
}



public class StreamScanner
{
	private readonly char[] _c = { ' ' };
	private int _index = -1;
	private string[] _input = new string[0];
	private readonly System.IO.StreamReader _sr = new System.IO.StreamReader(Console.OpenStandardInput());

	public T Next<T>()
	{
		if (_index == _input.Length - 1)
		{
			_index = -1;
			while (true)
			{
				string rl = _sr.ReadLine();
				if (rl == null)
				{
					if (typeof(T).IsClass) return default(T);
					return (T)typeof(T).GetField("MinValue").GetValue(null);
				}
				if (rl != "")
				{
					_input = rl.Split(_c, StringSplitOptions.RemoveEmptyEntries);
					break;
				}
			}
		}
		return (T)Convert.ChangeType(_input[++_index], typeof(T), System.Globalization.CultureInfo.InvariantCulture);
	}

	public T[] Next<T>(int x)
	{
		var ret = new T[x];
		for (var i = 0; i < x; ++i) ret[i] = Next<T>();
		return ret;
	}

	public T[][] Next<T>(int x, int y)
	{
		var ret = new T[y][];
		for (var i = 0; i < y; ++i) ret[i] = Next<T>(x);
		return ret;
	}
}