Program to implement the following Multiple Inheritance using interface

In multiple inheritance there are several super classes for a subclass. Java does not support Multiple inheritance. To achieve multiple inheritance in Java you have to use interface. The syntax for it is given below:
interface   <interface-name> {
    // variable declarations
 // Method declarations (no implementation)
}

The implements keyword is used to for implementing interface and extends keyword is used to extend the class. The syntax for extending class and implementing interface is:
class   <subclass-name>   extends   <superclass-name>   implements   <interface-name> {

 // Body of subclass
}

In this program, we have created an interface Exam which has one method percent_cal( ) without implementation (body). Then we declare the class Student having data members name, roll_no, marks1, marks2 and one method display( ). Finally we extend the Student class and implement the Exam interface in Result class. You must override all the methods which a interface contains.
PROGRAM 
import java.lang.*;
import java.io.*;

interface Exam {
 
 void percent_cal();
}

class Student {
 String name;
 int roll_no,mark1,mark2;
 
 Student(String n, int r, int m1, int m2) {
  
  name=n;
  roll_no=r;
  mark1=m1;
  mark2=m2;
 }
 
 void display() {
  
  System.out.println ("Name of Student: "+name);
  System.out.println ("Roll No. of Student: "+roll_no);
  System.out.println ("Marks of Subject 1: "+mark1);
  System.out.println ("Marks of Subject 2: "+mark2);
 }
}

class Result extends Student implements Exam {
 
 Result(String n, int r, int m1, int m2) {
  
  super(n,r,m1,m2);
 }
 
 public void percent_cal() {
  
  int total=(mark1+mark2);
  float percent=total*100/200;
  System.out.println ("Percentage: "+percent+"%");
 }
 
 void display() {
  
  super.display();
 }
}

public class MultipleInh {

 public static void main(String[] args) {
  
  Result R = new Result("Ragini",12,93,84);
  R.display();
  R.percent_cal();
 }
}
OUTPUT 
C:\>javac MultipleInh.java
C:\>java MultipleInh
Name of Student: Ragini
Roll No. of Student: 12
Marks of Subject 1: 93
Marks of Subject 2: 84
Percentage: 88.0%

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