大学有这样几类人员:学生、教师、职员和在职读书的教师。给出这几类人员的类描述。

// 补充必要的头文件（原代码缺失） #include <iostream> #include <string> using namespace std; // 基类：人员基本信息 class Person // 类名首字母大写，符合C++命名规范 { private: int age; // 年纪 string name; // 姓名 string identity; // 身份（原shenfen，英文更易读） public: // 优化点1：string类型默认值改为空字符串""，而非NULL Person(int m_age = 0, string m_name = "", string m_identity = "") : age(m_age), name(m_name), identity(m_identity) { // 可选：增加参数合法性检查，增强健壮性 if (age < 0) age = 0; // 年龄不能为负数 } // 虚函数，为多态提供基础 virtual void show() const { cout << "信息如下:" << endl; cout << "年龄:" << age << endl; cout << "姓名:" << name << endl; cout << "身份:" << identity << endl; } }; // 派生类：学生 class Student : public Person { private: string education; // 学历（原xueli，英文更易读） public: // 优化点1：string默认值改为"" Student(int age = 0, string name = "", string identity = "", string m_education = "") : Person(age, name, identity), education(m_education) {} void show() const override // 补充override关键字，明确重写基类虚函数 { Person::show(); cout << "学历:" << education << endl; } }; // 派生类：老师 class Teacher : public Person { private: string teachingSubject; // 教学科目（原Subject，命名更清晰） public: // 优化点1：string默认值改为""，修正参数名拼写错误（原m_subjcet） Teacher(int age = 0, string name = "", string identity = "", string m_subject = "") : Person(age, name, identity), teachingSubject(m_subject) {} void show() const override { Person::show(); cout << "教学科目:" << teachingSubject << endl; } }; // 派生类：职工 class Employee : public Person { private: string workUnit; // 工作单位（原unit，命名更清晰） public: // 优化点1：string默认值改为"" Employee(int age = 0, string name = "", string identity = "", string m_unit = "") : Person(age, name, identity), workUnit(m_unit) {} void show() const override { Person::show(); cout << "工作单位:" << workUnit << endl; } }; // 派生类：在职读书的老师（原Study_Work，类名更直观） class TeacherWithStudy : public Person { private: string teachingSubject; // 教学科目（命名和Teacher类保持一致） string education; // 学历（命名和Student类保持一致） public: // 优化点1：string默认值改为"" TeacherWithStudy(int age = 0, string name = "", string identity = "", string m_subject = "", string m_education = "") : Person(age, name, identity), teachingSubject(m_subject), education(m_education) {} void show() const override { Person::show(); cout << "教学科目:" << teachingSubject << endl; cout << "学历:" << education << endl; } }; int main() { Person* p1 = nullptr, * p2 = nullptr, * p3 = nullptr, * p4 = nullptr; // 创建各派生类对象 Student st(22, "王五", "学生", "高中生"); p1 = &st; p1->show(); cout << endl; Teacher te(30, "张三", "老师", "数学"); p2 = &te; p2->show(); cout << endl; Employee em(45, "老王", "职工", "保安"); p3 = &em; p3->show(); cout << endl; TeacherWithStudy sw(26, "李四", "在职读书老师", "大学英语", "研究生"); p4 = &sw; p4->show(); return 0; }