Inheritance in C#

This code demonstrates the use of single inheritance in C#. It the program there are two classes X and Y. Y is extending X here through inheritance. Each of these two classes have there own constructors, but we are passing the value to the base class constructor(X()) through the 'base' keyword.

 
class X
    {
        int a, b;
        public X(int a1, int b1)
        {
            a = a1;
            b = b1;
            Console.WriteLine("a={0}b={1}", a, b);
        }
    }
//Y extending the base class X
 class Y:X
 {
     public Y(int n, int m):base(n,m)
     {
         Console.WriteLine("n={0}m={1}",n,m);
     }
}
 class MainClass
    {
        static void Main(string[] args)
        {
            Y o = new Y(10,20);
        }
    }

OUTPUT

a=10b=20
n=10m=20