假设图书馆的图书包含书名、编号和作者属性，读者包含姓名和借书证属性，每们读者最多可借5本书。设计一个类object,从它派生出图书类book和读者类reader,在reader类中有一个rentbook()成员函数用于借阅图书。-The assumption that the library contains books title, number and author attributions, readers contain the name and library card attributes, each of their readers up to five books. Design of a class object, derived from its type library types of book and reader reader, the reader, there is a category rentbook () member function used to borrow books.