使用c++中的继承与派生，class类来编写模拟某单位的人事管理。人事信息主要包括：员工编号、所在部门、职务、薪资等级、薪资、联系方式等内容；部门信息主要包括：部门编号、部门名称等内容。完成以下操作：实现员工信息、部门信息的添加、修改、删除和查询。

好的，根据您的要求，我可以给您提供一份C++代码，实现人事管理系统的基本功能。请注意，以下代码仅供参考，您可以根据自己的需求进行修改和完善。

首先，我们需要定义两个类，一个是员工类，一个是部门类。代码如下：

#include <iostream>
#include <string>
#include <vector>

using namespace std;

class Employee {
public:
    Employee(int id, string dept, string position, int salary_level, double salary, string contact_info) :
        m_id(id), m_dept(dept), m_position(position), m_salary_level(salary_level), m_salary(salary), m_contact_info(contact_info) {}

    int get_id() const { return m_id; }
    string get_dept() const { return m_dept; }
    string get_position() const { return m_position; }
    int get_salary_level() const { return m_salary_level; }
    double get_salary() const { return m_salary; }
    string get_contact_info() const { return m_contact_info; }

    void set_dept(string dept) { m_dept = dept; }
    void set_position(string position) { m_position = position; }
    void set_salary_level(int salary_level) { m_salary_level = salary_level; }
    void set_salary(double salary) { m_salary = salary; }
    void set_contact_info(string contact_info) { m_contact_info = contact_info; }

private:
    int m_id;
    string m_dept;
    string m_position;
    int m_salary_level;
    double m_salary;
    string m_contact_info;
};

class Department {
public:
    Department(int id, string name) : m_id(id), m_name(name) {}

    int get_id() const { return m_id; }
    string get_name() const { return m_name; }

    void set_name(string name) { m_name = name; }

private:
    int m_id;
    string m_name;
};

接下来，我们需要定义一个管理类，用于管理员工和部门信息的添加、修改、删除和查询。代码如下：

class HRSystem {
public:
    void add_employee(int id, string dept, string position, int salary_level, double salary, string contact_info) {
        Employee emp(id, dept, position, salary_level, salary, contact_info);
        m_employees.push_back(emp);
    }

    void add_department(int id, string name) {
        Department dept(id, name);
        m_departments.push_back(dept);
    }

    void update_employee(int id, string dept, string position, int salary_level, double salary, string contact_info) {
        for (auto& emp : m_employees) {
            if (emp.get_id() == id) {
                emp.set_dept(dept);
                emp.set_position(position);
                emp.set_salary_level(salary_level);
                emp.set_salary(salary);
                emp.set_contact_info(contact_info);
                break;
            }
        }
    }

    void update_department(int id, string name) {
        for (auto& dept : m_departments) {
            if (dept.get_id() == id) {
                dept.set_name(name);
                break;
            }
        }
    }

    void delete_employee(int id) {
        for (auto it = m_employees.begin(); it != m_employees.end(); ++it) {
            if (it->get_id() == id) {
                m_employees.erase(it);
                break;
            }
        }
    }

    void delete_department(int id) {
        for (auto it = m_departments.begin(); it != m_departments.end(); ++it) {
            if (it->get_id() == id) {
                m_departments.erase(it);
                break;
            }
        }
    }

    void print_employee(int id) const {
        for (auto& emp : m_employees) {
            if (emp.get_id() == id) {
                cout << "ID: " << emp.get_id() << endl;
                cout << "Department: " << emp.get_dept() << endl;
                cout << "Position: " << emp.get_position() << endl;
                cout << "Salary Level: " << emp.get_salary_level() << endl;
                cout << "Salary: " << emp.get_salary() << endl;
                cout << "Contact Info: " << emp.get_contact_info() << endl;
                break;
            }
        }
    }

    void print_department(int id) const {
        for (auto& dept : m_departments) {
            if (dept.get_id() == id) {
                cout << "ID: " << dept.get_id() << endl;
                cout << "Name: " << dept.get_name() << endl;
                break;
            }
        }
    }

private:
    vector<Employee> m_employees;
    vector<Department> m_departments;
};

最后，我们可以在主函数中调用这些函数，完成人事管理系统的基本功能。代码如下：

int main() {
    HRSystem hr_system;

    // 添加员工和部门信息
    hr_system.add_employee(1001, "Sales", "Sales Manager", 3, 5000.0, "sales@company.com");
    hr_system.add_employee(1002, "Marketing", "Marketing Manager", 3, 5000.0, "marketing@company.com");
    hr_system.add_employee(1003, "HR", "HR Manager", 3, 5000.0, "hr@company.com");
    hr_system.add_department(1, "Sales");
    hr_system.add_department(2, "Marketing");
    hr_system.add_department(3, "HR");

    // 修改员工和部门信息
    hr_system.update_employee(1001, "Sales", "Sales Director", 4, 6000.0, "sales_director@company.com");
    hr_system.update_department(1, "Sales Department");

    // 删除员工和部门信息
    hr_system.delete_employee(1002);
    hr_system.delete_department(3);

    // 查询员工和部门信息
    hr_system.print_employee(1001);
    hr_system.print_department(1);

    return 0;
}

以上就是一个简单的人事管理系统的实现，您可以根据自己的需求进行修改和完善。希望能对您有所帮助！