类的设计，选1：设计一个用于人事管理的People（人员）类。

* 考虑到通用性，这里只抽象出所有类型人员都具有的属性：

* number（编号）、sex（性别）、birthday（出生日期）、id（身份证号）等。

* 其中“出生日期”声明为一个“日期”类内嵌子对象。用成员函数实现对人员信息的录入和显示。

* 要求至少包括：构造函数和析构函数、拷贝构造函数。-Design of class, choose 1: the design of a People for the personnel management (personnel) class.

In view of universality, here only abstracts properties of all types of personnel have the:

Number (serial number), sex (sex), birthday (date of birth), ID (ID) etc..

The　date of birth　the statement as a　date　class of embedded objects. A member function to achieve the personnel information input and display.

Requirements include at least: the constructor and destructor, copy constructor.