/*
 *  C# Program to Illustrate Hierarchical Inheritance
 */
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
namespace Inheritance
{
class Program
{
    static void Main(string[] args)
    {
        Principal g = new Principal();
        g.Monitor();
        Teacher d = new Teacher();
        d.Monitor();
        d.Teach();
        Student s = new Student();
        s.Monitor();
        s.Learn();
        Console.ReadKey();
    }
    class Principal
    {
        public void Monitor()
        {
            Console.WriteLine("Monitor");
        }
    }
    class Teacher : Principal
    {
        public void Teach()
        {
            Console.WriteLine("Teach");
        }
    }
    class Student : Principal
    {
        public void Learn()
        {
            Console.WriteLine("Learn");
        }
    }
}
}

/*
Monitor
Monitor
Teach
Monitor
Learn