using System;
using System.Collections.Generic;

public class MyClass
{ 
	public static void Main()
	{
		List<string> names = new List<string>() { "ccc", "xxx", "aaa","bbbb" };
		names.Sort();
		var result = String.Join(",", names.ToArray());
	   Console.Write(result);
	   Console.ReadKey();
	} 
}