CS 202, Fall 2007
Assignment #7, Problem 2

Ans) Private data members are hidden and are accessible only through public and 
protected member functions of base class. Protected access allows derived 
classes to access them directly, without using access functions.
Using private access there is function overhead and hence decrease in 
performance because we have to access private members through function calls, 
but private access supports better software engineering style by controlling 
access to private members through the base class interface.