Group A-Assignment no 9

Imagine a publishing company which does marketing for book and audiocassette versions.
Create a class publication that stores the title (a string) and price (type float) of a
publication. From this class derive two classes: book, which adds a page count (type int),
and tape, which adds a playing time in minutes (type float).
Write a program that instantiates the book and tape classes, allows user to enter data and
displays the data members. If an exception is caught, replace all the data member values
with zero values.


Answer:

Follow the following steps
1.Create a base class publication.
2.title and price data members are declared as protected members.
3.write a default and parameterised  construtor in a base class to initialize data members(i.e title and price) 
4. write a derived class book which has pagecount data member.
5.write a constructor of book class which has 3 parameters from which 2 are used to initialize data members of base class and one for its own.
6.write a display function to display a members of book (title and price inherited from base class publication and pagecount(its own))
7.Follow the same steps for CD class


Program:

#include <iostream>
#include<string>
using namespace std;
class publication
{
    protected:
    string title;
    float price;
   
    public:
    publication()
    {
        title=" ";
        price=0.0;
        
        }
        publication(string t,float p)
        {
            title=t;
            price=p;
            
            }
           
            
    
    };
    class book : public publication
    {
        int pagecount;
        public:
        book()
        {
            pagecount=0;
            
        }
        //After : base class constructor is called
        book(string t,float p,int pc):publication(t,p)
        {
            
            pagecount=pc;
            
        }
     
     void display()
     {
        
          cout<<"title :"<<title<<endl;
                cout<<"Price: "<<price<<endl;
       
          cout<<"Pagecount :"<<pagecount<<endl;
         
        }
        
    };

 class CD : public publication
    {
        float time;
        public:
        CD()
        {
            time=0.0;
            
        }
        //After : base class constructor is called
        CD(string t,float p,float tim):publication(t,p)
        {
            
            time=tim;
            
        }
     
     void display()
     {
         cout<<"title :"<<title<<endl;
                cout<<"Price: "<<price<<endl;
       
          cout<<"time in minutes :"<<time<<endl;
         
        }
        
    };
int main()
{
    cout<<endl<<"Book data"<<endl;
    book b("C++",230,300);
    b.display();
    cout<<endl<<"CD Data"<<endl;
    CD c("programming",100,120.5);
    c.display();
    return 0;
        }


//OUTPUT

Book data title :C++ Price: 230 Pagecount :300 CD Data title :programming Price: 100 time in minutes :120.5