Question

Please help me to write a program in C++ with comments and to keep it simple as possible.

Thank you!

C++ Functions (20 points) Convert the following programming assignment that you have done before using C++ Class. Create constructors, set and get methods and all other necessary methods. Create your own main 0 program to thoroughly test whether your class design works well. Write a program to calculate a volume and side surface of a cylinder with a given radinus and length respectively. Write a function for each calculation. Display the results in a readable format with two decimal points. Below shows information on how to calculate the volume and the side surface of a cylinder, and how the function should be designed. Volume of cylinder The volume, V, of a cylinder is given by this formula; r is the cylinder's radius, and L is its length Using this formula, write a C++fimction named cyvol() that accepts a cylinder's radius and length and return its vohme. Surface area The side surface area, S, of a cylinder is given by this formula r is the cylinder's radius, and 1 is its length Using this formula, write a C++function named surfarea) that accepts a cylinder's radnus and length and return its side surface area.

Here is my program I have done before and that need to be change:

#include <iostream>

#include <iomanip>

using namespace std;

// function prototype – returning one value

double cylvol(double, double); // Note: two data types inside brackets

double surfarea(double, double); // Note: two data types inside brackets

int main()

{

double r, l, V, S;

cout << setprecision(2) << fixed; // Note: display the results in a readable format with two decimal points

cout << "Input the radius of the cylinder and its length by a space: ";

cin >> r >> l;

V = cylvol(r, l); // Note: passing two numbers to function

S = surfarea(r, l);

cout << "The volume of a cylinder is: " << V << endl;

cout << "The side surface area of a cylinder is: " << S << endl;

system("pause");

return 0;

}

double cylvol(double r, double l) // Note: receiving two numbers

{

double V;

V = 3.14*(r*r*l);

return V;  

}

double surfarea(double r, double l) // Note: receiving two numbers

{

double S;

S = 2 * 3.14*(r*l);

return S;  

}

Answer 1

#include <iostream>
#include <iomanip>

using namespace std;

class cylinder{
private:
    double r, l;
public:
    cylinder(double r, double l);
    double cylvol(); // Note: two data types inside brackets
    double surfarea(); // Note: two data types inside brackets
};

double cylinder::cylvol() // Note: receiving two numbers
{
    double V;
    V = 3.14 * (r * r * l);
    return V;
}

double cylinder::surfarea() // Note: receiving two numbers
{
    double S;
    S = 2 * 3.14 * (r * l);
    return S;
}

cylinder::cylinder(double r, double l) : r(r), l(l) {}

// function prototype – returning one value

int main() {
    double r, l, V, S;
    cout << setprecision(2) << fixed; // Note: display the results in a readable format with two decimal points
    cout << "Input the radius of the cylinder and its length by a space: ";
    cin >> r >> l;
    cylinder c(r, l);
    V = c.cylvol(); // Note: passing two numbers to function
    S = c.surfarea();
    cout << "The volume of a cylinder is: " << V << endl;
    cout << "The side surface area of a cylinder is: " << S << endl;
    system("pause");
    return 0;
}