Problem
Create a pricing system for a company that makes individualized computers, such as you might see on a Web site. There are two kinds of computers: laptops and desktop computers. The customer can select the processor speed, the amount of memory, and the size of the disk drive. The customer can also choose a CD drive (CD ROM, CD-RW), a DVD drive, or both. For laptops, there is a choice of screen size. Other options are a modem, a network card, or wireless network. You should have an abstract class Computer and derived classes Desk_Top and Lap_Top. Each derived class should have member functions for calculating the price of a computer given the base price plus the cost of the different options. You should have member functions for calculating memory price, hard drive price, and so on. There should be a member function to calculate shipping cost.