#if !defined(AFX_GAQUEEN_H__C26AE0A3_F9B4_426F_A324_B460CC7946CB__INCLUDED_) #define AFX_GAQUEEN_H__C26AE0A3_F9B4_426F_A324_B460CC7946CB__INCLUDED_ #if _MSC_VER > 1000 #pragma once #endif // _MSC_VER > 1000 class CGAQueen

上转型对象 1．实验目的 掌握上转型对象的使用。 2． 实验要求 要求有一个abstract类，类名为Employee，Employee的子类有YearWorker、MonthWorker和WeekWorker。YearWorker对象按年领取薪水，MonthWorker按月领取薪水，WeekWorker按周领取薪水。Employee有一个abstract方法： public abstract earnings() 子类必须重写父类的earnings()方法，给出各自领

* Coupling between classes and class libraries is a major maintenance * headache. To ease this problem, often the client talks to an * abstraction descr iption, which in turn calls an implementation. * Sometimes these must evolve - when o