Java Abstract Class Help

Question

import java.util.Scanner;

abstract class Shape {
protected int width;
abstract void area();
}

class Square extends Shape {

Square(int width) {
this.width = width;
}

void area() {
System.out.println(width * width);
}
}

class Circle extends Shape {

Circle(int width) {
this.width = width;
}

void area() {
System.out.println((width * width) * Math.PI);
}
}

public class Program {
public static void main(String[ ] args) {
Scanner sc = new Scanner(System.in);
int x = sc.nextInt();
int y = sc.nextInt();

Square a = new Square(x);
Circle b = new Circle(y);
a.area();
b.area();
}
}

This code here is from one of the Java challenges on sololearn, it works for 4/5 of the tests but the one it doesn't work for is hidden and I don't understand why it does not work for that test.

The only issue that I can see is that in my IDE it says that the abstract void area() method is never used.

Answer 1

Maby use Annotations like @Override above the area method but the program looks ok to me