设计一个图书馆馆藏系统，设计所有馆藏条目的基类为：classItemBase。实现用m_AllItemsCount对所有馆藏条目（item）进行计数的功能，并添加函数GetCount ()返回m_AllItemsCount的值；在ItemBase类中添加成员函数Getm_status()来返回m_status设计ItemBase类的公有继承类Book（书）和Media（电子资源），在Book类中添加私有变量m_ISBN（string类型），在Media类中添加私有变量m_Source（string类型），在Book和Media类中添加适当的函数，实现对Book和Media两个类中的所有变量进行访问；设计ItemBase类的私有继承类Thesis（毕业论文），添加私有变量m_Author（string类型）。在ItemBase和Thesis类中添加适当的函数，实现Thesis对类中的所有变量进行访问；

-The design of a library collection systems, the design of all the holdings entries base class: classItemBase. Achieve to count with m_AllItemsCount on all collection entries (item) and add GetCount () function returns the value of the m_AllItemsCount　in ItemBase class add member function Getm_status (), to public inheritance class Book return m_status design ItemBase class (book) and Media (electronic resources), add a private variable in the Book class m_ISBN (string type) in the Media class, add a private variable m_Source (string type), add the appropriate function in the Book and Media class to achieve the Book and Media access to all variables in a class　design the private inheritance ItemBase class Thesis (thesis), add private variables m_Author (string type). Add the appropriate function class ItemBase and Thesis Thesis on the class of all variables to be accessed