Answer to Question #160952 in C++ for Kefilwe Mamabolo

Question

A student in Programming 1 wants to know the surface area and volume of a cylindrical shape.

Figure 5.1: Example of a cylinder

Volume = PI(R^²) x height

Area = 2PI(R^²) x height + 2PI(R^²) 

5.1.1 Write a program that will assist the students:

5.1.2Create a C++ source file called Cylinder and save it in a file called Cylinder.cpp.

5.2 Create the following functions: 

5.2.1 calcVolume() This function will receive three parameters and it must then calculate 

and return the volume of a cylinder using the information given 

above.

5.2.2 calcArea() This function will receive three parameters and it must then calculate 

and return the area of a cylinder using the information given above.

5.2.3 main() NB: The functions must be implemented above the main.

Add all necessary pre-processor directives.

 Declare all constants and necessary variables.

 Prompt the user for the height of the cylinder, and the radius of

the base of the cylinder.

 Based on the users option :

o Do the relevant calculations by calling the correct 

function.

 Display the results of the desired measurement.

 If an invalid option is selected an appropriate error message

Answer 1

#include <iostream>
#include <cmath>
#define _USE_MATH_DEFINES

using namespace std;

double calcVolume(double height, double radius, double pi) {
  double volume;

  volume =  pi * (radius * radius) * height;

  return volume;
}

double calcArea(double height, double radius, double pi) {
  double area;

  area =  2 * pi * radius * height + 2 * pi * (radius * radius);

  return area;
}

int main() {
  double height, radius;
  double volume, area;

  cout << "Enter the height of the cylinder: ";
  cin >> height;

  if ( height <= 0 ) {
    cout << "Error: the height must be a positive number greater than zero";
    return 0;
  }

  cout << "Enter the radius of the base of the cylinder: ";
  cin >> radius;
  
  if ( radius <= 0 ) {
    cout << "Error: the radius must be a positive number greater than zero";
    return 0;
  }

  volume = calcVolume(height, radius, M_PI);

  area = calcArea(height, radius, M_PI);

  cout << "\n";

  cout << "The volume of the cylinder is " << volume << "\n";

  cout << "The area of the cylinder is " << area << "\n";
  
  return 0;
}