CalcInterface.java

class CalcuTest{
 public static void main(String[] args) {
 CalcInterface obj = new Calc();
 obj.sum();
 obj.sub();
 obj.multi();
 obj.div();
 }
}

interface CalcInterface {
 public void sum();

 public void sub();

 public void multi();

 public void div();
}

class Calc implements CalcInterface {
 int a = 99, b = 9;

 public void sum() {
 System.out.println("Sum : " + (a + b));
 };

 public void sub() {
 System.out.println("Sub : " + (a - b));
 }

 public void multi() {
 System.out.println("Multi : " + (a * b));
 }

 public void div() {
 System.out.println("Div : " + (a / b));
 }
}