Circle area and cylinder volume --- calling functions

Script

#include <iostream>
using namespace std;
#include <string>
#include <cmath>

const double PI=3.14159;


double getPositiveValueRadius(string message1)
{
        double number=0;

        do
        {
        cout << message1 << endl;
        cin >> number;
        }
        while (number <= 0);
        return number;
}

double getPositiveValueHeight(string message2)
{
        double number=0;

        do
        {
        cout << message2 << endl;
        cin >> number;
        }
        while (number <= 0);
        return number;

}

double areaOfCircle(double center_to_end)
{
        return PI*pow(center_to_end,2);
}

double volOfCylinder(double rad,double hght)
{
return PI*pow(rad,2)*hght;
}


int main()
{
        double radius = getPositiveValueRadius("Enter the radius of the circle/cylinder: ");
        double height = getPositiveValueHeight("Enter the height of the cylinder: ");
        double aCircle = areaOfCircle(radius);
        double vCylinder = volOfCylinder(radius,height);

        cout << "The area of the circle that has a radius of " << radius << " inches is " << aCircle << " square inches." << endl;
        cout << "The volume of the cylinder that has a radius of " << radius << " inches and ";
        cout << "height of " << height << " inches is " << vCylinder << " cubic inches." << endl;

}

Execution

Enter the radius of the circle/cylinder:

5

Enter the height of the cylinder:

10

The area of the circle that has a radius of 5 inches is 78.5397 square inches.

The volume of the cylinder that has a radius of 5 inches and height of 10 inches is 785.398 cubic inches.

Enter the radius of the circle/cylinder:

7.87

Enter the height of the cylinder:

21.39

The area of the circle that has a radius of 7.87 inches is 194.58 square inches.

The volume of the cylinder that has a radius of 7.87 inches and height of 21.39 inches is 4162.07 cubic inches.