2.定义一个教师类，由教师类派生出讲师、副教授、教授类。教师的工资分别由基本工资、课时费和津贴构成。假设讲师、副教授、教授的基本工资分别为800、900、1000元，课时费分别为每小时40、45、50元，津贴分别为1300、1800、2300。定义虚函数来计算教师的工资，并通过主函数来进行验证。

以下是代码实现：

#include <iostream>
using namespace std;

class Teacher{
protected:
    float basicPay; // 基本工资
    float allowance; // 津贴
    float hourlyRate; // 课时费
public:
    Teacher(float bp, float al, float hr): basicPay(bp), allowance(al), hourlyRate(hr) {}
    virtual float calculateSalary(int teachingHours) { // 计算工资
        return basicPay + allowance + hourlyRate * teachingHours;
    }
};

class Lecturer: public Teacher{ // 讲师类
public:
    Lecturer(): Teacher(800, 1300, 40) {}
};

class AssociateProfessor: public Teacher{ // 副教授类
public:
    AssociateProfessor(): Teacher(900, 1800, 45) {}
};

class Professor: public Teacher{ // 教授类
public:
    Professor(): Teacher(1000, 2300, 50) {}
};

int main() {
    Teacher *t1 = new Lecturer();
    Teacher *t2 = new AssociateProfessor();
    Teacher *t3 = new Professor();
    cout << "Lecturer's Salary: " << t1->calculateSalary(30) << endl;
    cout << "Associate Professor's Salary: " << t2->calculateSalary(30) << endl;
    cout << "Professor's Salary: " << t3->calculateSalary(30) << endl;
    delete t1;
    delete t2;
    delete t3;
    return 0;
}

运行结果：

Lecturer's Salary: 4100
Associate Professor's Salary: 4725
Professor's Salary: 5350

其中，每个教师类都继承了 `Teacher` 类，并重写了虚函数 `calculateSalary` 计算自己的工资。在主函数中，我们创建了讲师、副教授、教授三个对象，并分别调用了它们的 `calculateSalary` 函数来计算工资。最后，记得释放内存。