Head First C++ code for Duck Simulator : A Strategy Pattern

The very first chapter in the awesome Head First Design Patterns book explains 3 fundamental design principle that forms the basis of Strategy design pattern. These principles are

1. Identify the aspect of your application that vary and separate them from what stays the same.
2. Program to an interface, not an implementation.
3. Favor composition over inheritance.

The example code in Chapter 1 Intro to Design Patterns provide Java Implementation of Duck Simulator. I tried to write similar code in C++ that explains the Strategy Pattern used in the program. The behaviors of a duck that can vary (  Fly Behavior, Quack Behavior ) are encapsulated as family of classes and the non varying part ie Duck Class is base class for different types of ducks ( principle 1). Duck acts as client and make use of encapsulated family of behaviors/algorithms. This particular design is Strategy pattern and it defines a family of algorithms, encapsulates each one, and makes them interchangeable. Strategy lets the algorithm vary independently from clients that uses it.

Here is the class diagram of SimUDuck simulator

The c++ code is build using VS2010 IDE. You can download code from here.