c++a建立职工信息数据（包括职工号、姓名、性别、工资、出生时间、参加工作时间和年龄（必须计算得到）。），保存到文件中。 b建立职工信息简表（只含有姓名和年龄的职工信息简表）,保存 c使用继承的方法构造三个类（（即雇员类——虚基类，教师类和工人类——派生类）使用相应的对象放置10个（或以上）职工信息） d编写同名display()成员函数(输出数组的内容) e按不同类别输出职工信息（先排序再输出） f 按职工的年龄（必须计算得到）排序并输出 g运算符重载（输入输出），要求对“＜＜”和“＞＞”运算符进行重载。考虑到输人职工编号时，也会因不小心引入空格，而且名字中也需要有空格，所以重载“＞＞’’运算符时，需要满足这个要求。代码

以下是实现上述要求的代码：

#include <iostream>
#include <fstream>
#include <cstring>
#include <algorithm>
using namespace std;

class Employee {
protected:
    int id; // 职工号
    string name; // 姓名
    char gender; // 性别
    float salary; // 工资
    string birth; // 出生时间
    string work; // 参加工作时间
    int age; // 年龄
public:
    Employee() {}
    Employee(int id, string name, char gender, float salary, string birth, string work)
        : id(id), name(name), gender(gender), salary(salary), birth(birth), work(work) {
        age = 2021 - stoi(birth.substr(0, 4));
    }
    virtual ~Employee() {}
    virtual void display() {
        cout << "职工号：" << id << endl;
        cout << "姓名：" << name << endl;
        cout << "性别：" << gender << endl;
        cout << "工资：" << salary << endl;
        cout << "出生时间：" << birth << endl;
        cout << "参加工作时间：" << work << endl;
        cout << "年龄：" << age << endl;
    }
    friend ostream& operator<<(ostream& os, const Employee& emp) {
        os << emp.id << " " << emp.name << " " << emp.gender << " " << emp.salary << " " << emp.birth << " " << emp.work;
        return os;
    }
    friend istream& operator>>(istream& is, Employee& emp) {
        is >> emp.id >> emp.name >> emp.gender >> emp.salary >> emp.birth >> emp.work;
        emp.age = 2021 - stoi(emp.birth.substr(0, 4));
        return is;
    }
};

class Teacher : virtual public Employee {
private:
    string title; // 职称
public:
    Teacher() {}
    Teacher(int id, string name, char gender, float salary, string birth, string work, string title)
        : Employee(id, name, gender, salary, birth, work), title(title) {}
    void display() {
        cout << "职工号：" << id << endl;
        cout << "姓名：" << name << endl;
        cout << "性别：" << gender << endl;
        cout << "工资：" << salary << endl;
        cout << "出生时间：" << birth << endl;
        cout << "参加工作时间：" << work << endl;
        cout << "年龄：" << age << endl;
        cout << "职称：" << title << endl;
    }
};

class Worker : virtual public Employee {
private:
    string department; // 部门
public:
    Worker() {}
    Worker(int id, string name, char gender, float salary, string birth, string work, string department)
        : Employee(id, name, gender, salary, birth, work), department(department) {}
    void display() {
        cout << "职工号：" << id << endl;
        cout << "姓名：" << name << endl;
        cout << "性别：" << gender << endl;
        cout << "工资：" << salary << endl;
        cout << "出生时间：" << birth << endl;
        cout << "参加工作时间：" << work << endl;
        cout << "年龄：" << age << endl;
        cout << "部门：" << department << endl;
    }
};

bool cmpAge(Employee* a, Employee* b) {
    return a->age < b->age;
}

int main() {
    // a 建立职工信息数据，保存到文件中
    ofstream outfile("employee.txt");
    for (int i = 1; i <= 10; i++) {
        Employee* emp;
        if (i % 2 == 0) {
            emp = new Teacher(i, "张三", 'M', 5000 + i * 100, "1980-01-01", "2000-01-01", "副教授");
        } else {
            emp = new Worker(i, "李四", 'F', 3000 + i * 100, "1990-01-01", "2010-01-01", "技术部");
        }
        outfile << *emp << endl;
        delete emp;
    }
    outfile.close();

    // b 建立职工信息简表，保存到文件中
    ifstream infile("employee.txt");
    ofstream outfile2("simple.txt");
    while (!infile.eof()) {
        Employee* emp = new Employee();
        infile >> *emp;
        outfile2 << emp->name << " " << emp->age << endl;
        delete emp;
    }
    infile.close();
    outfile2.close();

    // c 构造三个类，放置10个职工信息
    Employee* empArr[10];
    for (int i = 1; i <= 10; i++) {
        if (i % 2 == 0) {
            empArr[i - 1] = new Teacher(i, "张三", 'M', 5000 + i * 100, "1980-01-01", "2000-01-01", "副教授");
        } else {
            empArr[i - 1] = new Worker(i, "李四", 'F', 3000 + i * 100, "1990-01-01", "2010-01-01", "技术部");
        }
    }

    // d 输出数组的内容
    for (int i = 0; i < 10; i++) {
        empArr[i]->display();
        cout << endl;
    }

    // e 按不同类别输出职工信息（先排序再输出）
    sort(empArr, empArr + 10, cmpAge);
    cout << "按年龄排序：" << endl;
    for (int i = 0; i < 10; i++) {
        empArr[i]->display();
        cout << endl;
    }

    // f 输出 Teacher 类型的职工信息
    cout << "Teacher 类型的职工信息：" << endl;
    for (int i = 0; i < 10; i++) {
        Teacher* t = dynamic_cast<Teacher*>(empArr[i]);
        if (t) {
            t->display();
            cout << endl;
        }
    }

    // g 运算符重载
    cout << "请输入职工信息（职工号 姓名 性别 工资 出生时间 参加工作时间）：" << endl;
    Employee e;
    cin >> e;
    cout << "输入的职工信息为：" << endl;
    cout << e << endl;

    return 0;
}