Java shapes only test case 3 failed

Question

Hello. I leave here the URL to my code. Every test case is passed but the third one. What's wrong? I checked everything over and over again, but the third test case is always failing and I see nothing strange.

https://code.sololearn.com/cA13a1977a18/#java

Answer 1

Floating point error.
Change the Circle's area print to:
Math.PI*width*width
Having those parentheses can cause a floating point error in this instance as doubles are prone to do that

Answer 2

Hey, maybe late but the problem is the order of the area calculation:

Correct order would be like this: Math.PI*Width*Width

Different distributions such as:

Width*Width*Math.PI
Width*Math.PI*Width
And so...

Would likely generate floating point inaccuracy.

Answer 3

Odyel Thank you! However, I don't get it. Both Math.PI and Math.pow are doubles. I wondered if that floating point error you say might be due to the mathematical aberration that doubles commit sometimes. Isn't it?

By the way, I had to delete both Math.pow in Square and Circle classes. This way, the problem in Circle is out and at the Square class I can spare casting to int.

Answer 4

import java.util.Scanner;
abstract class Shape {
int width;
abstract void area();
}

class Square extends Shape{
public int area2;
public Square(int x)
{
width=x;
}
public void area()
{
area2=width*width;
System.out.println(area2);

}
}
class Circle extends Shape {
public double area1;
public Circle(int y)
{
width=y;
}
public void area()
{
area1=Math.PI*width*width;
System.out.println(area1);
}
}

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();
}
}