constructors and destructors in c#

Program to implement constructors and destructors in c#

using System;
using System.Collections.Generic;
using System.Text;

namespace ConsoleApplication30
{
class a
{
public int s, d;
public a()
{
Console.WriteLine("constructor--base class a");
}
~a()
{
Console.WriteLine("destructor--base class a");
}

public void display()
{
Console.WriteLine(s);
Console.WriteLine(d );
}
}

class b : a
{

public b()
{
Console.WriteLine("constructor--derived class b");
}
~b()
{
Console.WriteLine("destructor--derived class b");
}
}
}

class c:a

{

static void Main(string[] args)
{

b b1 = new b();
b1.d = 34;

}
}