Problem
Give the definition of a class named Doctor whose objects are records for a clinic's doctors. This class will be a derived class of the class SalariedEmployee given in Display 14.4. A Doctor record has the doctor's specialty (such as "Pediatrician," "Obstetrician," "General Practitioner," etc., so use type string), and office visit fee (use type double). Be sure your class has a reasonable complement of constructors and accessor methods, an overloaded assignment operator, and a copy constructor. Write a driver program to test all your methods.