Question

Please answer it in C++

(a) Declare a class called Book representing a textbook.     

A textbook has a title (eg. “Programming in C++”)

A textbook has an author (eg. “Helen Johnstone”)

A textbook has a size in number of pages (eg. 550)

A textbook has a price (eg. $135.99).

These attributes should be represented as the data members of the class and be hidden from the outside of the class.

The class should also have a constructor used to initialise the data members of the objects of this class when they are created. The default values for the data members will be set to 0 for all numerical data members and to “unknown” for the string data members.

The class should also have a void member function called show() with no parameters which, when invoked will print the book attributes on a single line, on the screen.

(b) Given the class definition in part a above, write two statements that would create two Book objects b1 and b2, first one with the default characteristics, and the second one with the following characteristics:

            Title: Thinking in C++

            Author: Bruce Eckel

            Size: 575 pages

            Price: $45.00

Answer 1

Please see the below Output:

Please find the below code:

// C++ program to demonstrate 
// accessing of data members 

#include <bits/stdc++.h> 
using namespace std; 
class Book 
{ 
        // Access specifier 
        private: 

        // Data Members 
        string title; 
        string author; 
        int numberOfPages;
        double price;
    
    public: 
     //Constructor
     Book()
     {
         title = "Unknown";
         author = "Unknown";
         numberOfPages = 0;
         price = 00.00;
     }
     
        // Member Functions() 
        void show() 
        { 
          cout << "Title: " << title << "  Author: " << author  << " Size: " << numberOfPages << " pages " << " Price: $" << price <<endl; 
        } 
        
        // Member Functions() 
        void show(string stitle, string sauthor, int inumberofpage, double dprice) 
        { 
          cout << "Title: " << stitle <<endl << "Author: " << sauthor <<endl << "Size: " << inumberofpage << " pages "<<endl << "Price: $" << dprice <<endl; 
        } 
}; 

int main() { 

        // Declare an object of class geeks 
        Book obj1; 
        Book obj2;
        
        // accessing member function 
        obj1.show(); 
        
                // accessing member function 
        obj2.show("Thinking in C++","Bruce Eckel",575,45.00); 
        
        return 0; 
}