Multiple Inheritance in java program

import java.util.*;

import java.io.*;

class c1

{

int size=20;

void ln()

{

System.out.print(size);

}

}

interface intf

{

int breadth=40;

void br();

}

public class c3 extends c1 implements intf

{

public static void primary(String[] args)

{

c3 c= new c3();

c.ln();

c.br();

}

public void br()

{

System.out.print(breadth);

}

}