A book shop maintains the inventory of books that are being sold at the shop. The list includes details such as author, title, price, and stock position. Whenever a customer wants a book, he informs the salesperson. The salesperson inputs the title and author, and the system searches the list and displays whether it is available or not; if it is not, an appropriate message is displayed. If it is$,$ then the system displays the book details and requests for the number of copies requested. If the requested number is less than or equal to the stock, the total cost of the requested copies is displayed; otherwise, the message "Required copies not in stock" is displayed. Write an interactive C$++$ program using a class called book with suitable member functions and constructors.