C# Hello World

using System;

namespace myApp
{
    class Program
    {
        static void Main(string[] args)
        {
            Console.WriteLine("Hello World!");
        }
    }
}

using System;
namespace HelloWorld
{
    class Hello
{         
        static void Main(string[] args)
        {
          Console.WriteLine("Hello World!");
        }
    }
}

// Hello World! program
using System;
 
namespace HelloWorld
{
    class Hello {         
        static void Main(string[] args)
        {
            Console.WriteLine("Hello World!");
        }
    }
}

class Program
{
  static void Main(string[] args)
  {
    System.Console.WriteLine("Hello, World!");
  }
}