using System;
namespace Test
{
public class Base
{
public void Print()
{
Console.WriteLine(Operate(8, 4));
}
protected virtual int Operate(int x, int y)
{
return x + y;
}
}
}
namespace Test
{
public class OnceChild : Base
{
protected override int Operate(int x, int y)
{
return x - y;
}
}
}
namespace Test
{
public class TwiceChild : OnceChild
{
protected override int Operate(int x, int y)
{
return x * y;
}
}
}
namespace Test
{
public class ThirdChild : TwiceChild
{
}
}
namespace Test
{
public class ForthChild : ThirdChild
{
protected new int Operate(int x, int y)
{
return x / y;
}
}
}
namespace Test
{
class Program
{
static void Main(string[] args)
{
Base b = null;
b = new Base();
b.Print();
b = new OnceChild();
b.Print();
b = new TwiceChild();
b.Print();
b = new ThirdChild();
b.Print();
b = new ForthChild();
b.Print();
}
}
}