//C# Inheritance(Multilevel)

using System;

public class Program

{

    // Parent Class Definition

    public class Teacher

    {

        public string name;

        public int age;

        public Teacher()

        {

            Console.WriteLine("Parent class constructor invoked");

        }

        public void displayDetails()

        {

            Console.WriteLine("Name : {0}, Age : {1}",name,age);

        }

        public void calculateSalary(int baseSalary)

        {

            Console.WriteLine("Total Salary of {0} is {1}",name,(baseSalary+0.3*baseSalary));

        }   

    }

    // Child Class Definition

    public class Student : Teacher // Inhrited from Teacher Class

    {

        public int _1subMarks;

        public int _2subMarks;

        public int _3subMarks;

        public Student()

        {

            Console.WriteLine("Child class constuctor Inherited from Parent class");

        }

        public void displayMarks(int a,int b,int c)

        {

            _1subMarks = a;

            _2subMarks = b;

            _3subMarks = c;

            Console.WriteLine("Marks of {0} \nMaths : {1} ,Science : {2}, English : {3}",name,_1subMarks,_2subMarks,_3subMarks);

        }

    }

    // Grand Child Definition

    public class Result : Student // Inherited from Student class

    {

        int totalPercent;

        public Result()

        {

            Console.WriteLine("Grand Child Class Inheited From Child class");

        }

        public int marksAcheived(int a,int b,int c)

        {

            totalPercent = (a+b+c)/3;

            return totalPercent;    

        }

    }

    // Main Method definition

    public static void Main()

    {

        //Parent Class Object

        Teacher t = new Teacher();

        t.name = "Viswanath";

        t.age = 49;

        t.displayDetails();

        t.calculateSalary(50000);

        Console.WriteLine("\n");

        //Child Class Object

        Student s = new Student();

        s.name = "Rishab";

        s.age = 23;

        s._1subMarks = 92; // Hard code is Usually Not a good Programming Practice,anyhow it could be replaced by user inputs

        s._2subMarks = 86;

        s._3subMarks = 78;

        s.displayMarks(s._1subMarks,s._2subMarks,s._3subMarks);

        Console.WriteLine("\n");

        //Grand Child Class Object

        Result r = new Result();

        int percentMarks = r.marksAcheived(s._1subMarks,s._2subMarks,s._3subMarks); 

        Console.WriteLine("Total Percentage Acheived by {0} is {1}",s.name,percentMarks);

    }

}