Question

This is probably an easy one, but is the right way to calculate volume for a sphere in C++? My getArea() seems to be right, but when I call getVolume() it doesn’t output the right amount. With a sphere of radius = 1, it gives me the answer of pi, which is incorrect:

double Sphere::getArea() const
{
    return 4 * Shape::pi * pow(getZ(), 2);
}

double Sphere::getVolume() const
{
    return (4 / 3) * Shape::pi * pow(getZ(), 3);
}

Answer 1

You’re using integer division in (4 / 3). Instead, use floating point division: (4.0 / 3.0).

4/3 is 1, because integer division only produces integers. You can confirm this by test code: std::cout << (4/3) << std::endl;.