Program for Multilevel Inheritance

import javax.swing.JOptionPane;

class student

{

            int rno;

            void readdata1()

            {

            rno=Integer.parseInt(JOptionPane.showInputDialog("Enter roll number"));

            }

            void printdata1()

            {

            System.out.println("Roll Number="+rno);

            }

}

class exam extends student

{

            int m1,m2,m3;

            void readdata2()

            {

            readdata1();

            m1=Integer.parseInt(JOptionPane.showInputDialog("Enter sub1 marks"));

            m2=Integer.parseInt(JOptionPane.showInputDialog("Enter sub2 marks"));

            m3=Integer.parseInt(JOptionPane.showInputDialog("Enter sub3 marks"));

            }

            void printdata2()

            {

            printdata1();

            System.out.println("Sub 1 marks="+m1);

            System.out.println("Sub 2 marks="+m2);

            System.out.println("Sub 3 marks="+m3);

            }

}

class results extends exam

{

            int avg;

            void printdata3()

            {

            printdata2();

            avg=(m1+m2+m3)/3;

            if(avg<35)

            System.out.println("FAIL");

            else if(avg>=35 && avg<50)

            System.out.println("THIRD CLASS");

            else if(avg>=50 && avg<60)

            System.out.println("SECOND CLASS");

            else if(avg>=60 && avg<75)

            System.out.println("FIRST CLASS");

            else if(avg>=75)

            System.out.println("DISTINCTION");

            }

}

class mi

{

            public static void main(String[] args)

            {

                        results obj=new results();

                        obj.readdata2();

                        obj.printdata3();

            }

}