掌握继承和派生的定义，派生类的定义方法和继承方式。
掌握派生类中的构造函数的使用。
掌握多重继承的概念、定义方法、多重继承派生类构造函数的执行顺序。
掌握虚基类的概念和定义方法。
定义一个基类有姓名、性别、年龄；再由基类派生出教师类和学生类，教师类增加工号、职称和工资，学生类增加学号、班级、专业和入学成绩；由学生类和教师类派生在职研究生类和在读教师类，在职研究生类增加工作单位。(First, the purpose of the experiment　　　　　　(1) master the definition of inheritance and derivation, the definition method and inheritance mode of derived classes.　　　　　　(2) master the use of constructors in derived classes.　　　　　　(3) master the concept of multiple inheritance, the definition method, and the sequence of multiple inheritance successor constructors.　　　　　　(4) grasp the concept and definition method of virtual base class.　　　　　　Two. The content of the experiment　　　　　　A base class is defined as name, sex and age; teachers and students are derived from the base class. The class number, job title and salary are added to the class. The student class increases school number, class, specialty and school grade. Students and teachers are derived from the class and teacher class, and the on-the-job postgraduate classes are added to work units.　　　　　　Three. Experimental requirements)