Assignment from my "Object Oriented Programming" course
##v.1 The original version based on the material learn from pervious course, and text parsing with vector STL.
##v.2 Use a vector "Bag" to store the objects.
##v.3 Add an ostream reference to the object.
##v.4 Use the "const" keyword.
##v.5 Inheritance.
##v.6 Polymorphism.
##v.7 GUI Programming With The MFC.
The END.