设计一个用于人事管理的People(人员)类

 #include <iostream>
 #include <string>
 using namespace std; 

 class Date //日期类
 {
 private:
 int year;
 int month;
 int day;
 public:
 Date(){} //默认构造
 Date(int y,int m,int d) //带参构造
 {
 year=y;
 month=m;
 day=d;
 }
 void set() //设置数据函数
 {
 cin>>year>>month>>day;
 }
 void display() //显示函数
 {
 cout<<year<<"年"<<month<<"月"<<day<<"日";
 }
 }; 

 class Person //人员类
 {
 private:
 int num;
 char sex;
 Date birthday;
 char ID[];
 public:
 Person(){} //默认构造
 Person(int n,int y,int m,int d,char id[],char s='m'):birthday(y,m,d)
 {
 num=n;
 sex=s;
 strcpy(ID,id);
 } //有默认值的带参构造
 Person(Person& p) //拷贝构造
 {
 num=p.num;
 sex=p.sex;
 birthday=p.birthday;
 strcpy(ID,p.ID);
 }
 void input() //输入函数
 {
 cout<<"录入数据："<<endl;
 cout<<"编号：";
 cin>>num;
 cout<<"性别(m/f)：";
 cin>>sex;
 cout<<"生日：";
 birthday.set();
 cout<<"身份证号：";
 cin>>ID;
 ID[]='\0';
 cout<<endl;
 }
 void output() //输出函数
 {
 cout<<"编号："<<num<<endl;
 cout<<"性别："<<sex<<endl;
 cout<<"生日：";
 birthday.display();
 cout<<endl;
 cout<<"身份证号："<<ID<<endl;
 }
 ~Person() //析构函数
 {
 cout<<" "<<num<<"号人员已经录入"<<endl;
 }
 }; 

 int main()
 {
 Person p1;
 p1.input();
 p1.output();
 return ;
 }