Question

Write a class named HalfOpenCylinder that has two data members: a double for the height in inches and a double for the radius in inches. It should have a constructor that takes two parameters and uses them to initialize the data members. It should have a default constructor that initializes the height to 10 and the radius to 2. It should have a method named surfaceArea that returns the the surface area (in square inches) of a cylinder with that height and radius which is closed on one end but open on the other. For pi, use a value of 3.14159. Write a class named Vase that has two data members: a HalfOpenCylinder that gives the dimensions of the vase and a double that gives the cost per square inch for the vase. It should have a constructor that takes two parameters and uses them to initialized the data members. It should have a method named totalCost that returns the surface area of the vase multiplied by its cost per square inch. It should have a method named costsMoreThan that takes a Vase parameter and returns true if the Vase the method is called on costs more than the Vase that was passed as a parameter. Otherwise it should return false. Here's one simple example of how your classes could be used: HalfOpenCylinder hoc1; Vase vase1(hoc1, 0.12); cout << vase1.totalCost() << endl; HalfOpenCylinder hoc2(80.4, 13); Vase vase2(hoc2, 0.2); // std::boolalpha prints Boolean values as "true" or "false" instead of an integer value cout << std::boolalpha << vase1.costsMoreThan(vase2) << endl; Because Vase.hpp needs to know what a HalfOpenCylinder is, it will need to #include HalfOpenCylinder.hpp. In your compile command, you need to list all of the .cpp files that you are compiling together. You do not need to list any .hpp files - those are included by the #include statements. The files must be named: HalfOpenCylinder.hpp, HalfOpenCylinder.cpp, Vase.hpp, Vase.cpp

Answer 1

Here is the completed code for this problem. Comments are included, go through it, learn how things work and let me know if you have any doubts or if you need anything to change. If you are satisfied with the solution, please rate the answer. Thanks

//HalfOpenCylinder.hpp file

#ifndef HalfOpenCylinder_H

#define HalfOpenCylinder_H

class HalfOpenCylinder{

                //attributes

                double height;

                double radius;

                public:

                //constructor taking values for height and radius

                HalfOpenCylinder(double h,double r);

                //default constructor

                HalfOpenCylinder();

                //returns the surface area

                double surfaceArea() const;

};

#endif

//end of HalfOpenCylinder.hpp file

//HalfOpenCylinder.cpp file

#include "HalfOpenCylinder.hpp"

//implementation of all methods

HalfOpenCylinder::HalfOpenCylinder(){

                height=10;

                radius=2;

}

HalfOpenCylinder::HalfOpenCylinder(double h, double r){

                height=h;

                radius=r;

}

double HalfOpenCylinder::surfaceArea() const{

                double pi=3.14159;

                //finding the surface area (in square inches) of a cylinder

                //which is closed on one end but open on the other.

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

                return area;

}

//end of HalfOpenCylinder.cpp file

//Vase.hpp file

#ifndef Vase_H

#define Vase_H

#include "HalfOpenCylinder.hpp"

class Vase{

                //attributes

                HalfOpenCylinder cylinder;

                double cost_per_sq_inch;

                public:

                //public methods

                Vase(HalfOpenCylinder c, double cost);

                double totalCost() const;

                bool costsMoreThan(Vase other) const;

               

};

#endif

//end of Vase.hpp file

//Vase.cpp file with main method

#include "Vase.hpp"

#include <iostream>

using namespace std;

//implementing all methods

Vase::Vase(HalfOpenCylinder cyl,double c){

                cylinder=cyl;

                cost_per_sq_inch=c;

}

double Vase::totalCost() const{

                return cylinder.surfaceArea()*cost_per_sq_inch;

}

bool Vase::costsMoreThan(Vase other) const{

                return totalCost()>other.totalCost();

}

//main method for testing

int main(){

                HalfOpenCylinder hoc1;

                Vase vase1(hoc1, 0.12);

                cout << vase1.totalCost() << endl;

                HalfOpenCylinder hoc2(80.4, 13);

                Vase vase2(hoc2, 0.2);

                // std::boolalpha prints Boolean values as "true" or "false" instead of an integer value

                cout << std::boolalpha << vase1.costsMoreThan(vase2) << endl;

}

/*OUTPUT*/

16.5876

false