Question

Creating a Class in C++

Summary

In this lab, you create a programmer-defined class and then use it in a C++ program. The program should create two Rectangle objects and find their area and perimeter.

Instructions

Ensure the class file named Rectangle.cpp is open in your editor.

In the Rectangle class, create two private attributes named length and width. Bothlength and width should be data type double.

Write public set methods to set the values for lengthand width.

Write public get methods to retrieve the values for length and width.

Write a public calculateArea()method and a public calculatePerimeter()method to calculate and return the area of the rectangle and the perimeter of the rectangle.

Open the file named MyRectangleClassProgram.cpp.

In the MyRectangleClassProgram, create two Rectangle objects named rectangle1 and rectangle2 using the default constructor as you saw in MyEmployeeClassProgram.cpp.

Set the length of rectangle1to 10.0 and the width to 5.0. Set the length of rectangle2to 7.0 and the width to 3.0.

Print the value of rectangle1’s perimeter and area, and then print the value of rectangle2’s perimeter and area.

Execute the program by clicking the Run button at the bottom of the screen

// This program uses the programmer-defined Rectangle class.
#include "Rectangle.cpp"
#include <iostream>
using namespace std;
int main()
{

Rectangle rectangle1;
Rectangle rectangle2;

rectangle1.setLength(10.0);
rectangle1.setWidth(5.0);
rectangle2.setLength(7.0);
rectangle2.setWidth(3.0);

cout << "Perimeter of rectangle1 is " << rectangle1.calculatePerimeter() << endl;
cout << "Area of rectangle1 is " << rectangle1.calculateArea() << endl;
cout << "Perimeter of rectangle2 is " << rectangle2.calculatePerimeter() << endl;
cout << "Area of rectangle2 is " << rectangle2.calculateArea() << endl;

return 0;
}

Answer 1

Rectangle.cpp

class Rectangle
{
private:
  
double Length,Width; //PRIVATE ATTRIBUTES LENGTH AND WIDTH
double Area,Perimeter; //PRIVATE ATTRIBUTES AREA AND PERIMETER

public:
  
double setLength(double a)
{
//PUBLIC METHOD TO SET VALUE OF LENGTH
Length=a;
return 0;
}
double setWidth(double b)
{
//PUBLIC METHOD TO SET VALUE OF WIDTH
Width=b;
return 0;
}
double getLength()
{
//PUBLIC METHOD TO GET THE VALUE OF LENGTH
return Length;
}
double getWidth()
{
//PUBLIC METHOD TO GET THE VALUE OF WIDTH
return Width;  
}
double calculatePerimeter()
{
//PUBLIC METHOD TO CALCULATE AND DISPLAY THE PERIMETER OF THE RECTANGLE
Perimeter=2*(Length+Width);
return Perimeter;
}
double calculateArea()
{
//PUBLIC METHOD TO CALCULATE AND DISPLAY THE AREA OF THE RECTANGLE
Area=Length*Width;
return Area;
}
};

Note: Copy the above code and save as Rectangle.cpp

MyRectangleClassProgram.cpp

#include "Rectangle.cpp" //IMPORTS THE CLASS FILE Rectangle.cpp
#include <iostream>

using namespace std;

int main()
{
Rectangle rectangle1; //rectangle1 is an object of Class Rectangle
Rectangle rectangle2; //rectangle2 is an object of Class Rectangle

rectangle1.setLength(10.0); //This code will set the value to the attribute Length of Object rectangle1
rectangle1.setWidth(5.0); //This code will set the value to the attribute Width of Object rectangle1
rectangle2.setLength(7.0); //This code will set the value to the attribute Length of Object rectangle2
rectangle2.setWidth(3.0); //This code will set the value to the attribute Width of Object rectangle2

//Following statement will calculate and display the Perimeter of Object rectangle1
cout << "Perimeter of rectangle1 is " << rectangle1.calculatePerimeter() << endl;
  
//Following statement will calculate and display the Area of Object rectangle1
cout << "Area of rectangle1 is " << rectangle1.calculateArea() << endl;
  
//Following statement will calculate and display the Perimeter of Object rectangle2
cout << "Perimeter of rectangle2 is " << rectangle2.calculatePerimeter() << endl;
  
//Following statement will calculate and display the Area of Object rectangle2
cout << "Area of rectangle2 is " << rectangle2.calculateArea() << endl;

return 0;
}

Note: Copy the code and save as MyRectangleClassProgram.cpp