class.cpp

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

using namespace std;

class Person{

private:
    string name;
    int age;


public:
    const string &getName() const {
        return name;
    }

    int getAge() const {
        return age;
    }

    void setName(const string &name) {
        Person::name = name;
    }

    void setAge(int age) {
        Person::age = age;
    }

};


class Student : public Person{

private:

    double toan, ly,hoa;

public:
    void setToan(double x){
        Student::toan = x;
    }

    void setLy(double x){
        Student::ly = x;
    }

    void setHoa(double x){
        Student::hoa = x;
    }

    double getToan(){
        return Student::toan;
    }

    double getLy(){
        return Student::ly;
    }

    double getHoa(){
        return Student::hoa;
    }

    double TB(){
        return (Student::getLy() + Student::getToan() + Student::getHoa()) / 3;
    }
};


class Teacher : public Person{

private:
    vector<Student> s;

public:

    void setStudent(Student student){
        Teacher::s.push_back(student);
    }

    vector<Student> getStudents(){
        return Teacher::s;
    }

    Student getGoodStudent(){

        Student good;

        if(Teacher::s.size() == 0){

            cout << "Ko co SV nao";
            return good;
        }

        good = Teacher::s[0];
        double tb = good.TB();
        for(int i = 1; i < Teacher::s.size(); i++){
            if(Teacher::s[i].TB() > tb){
                good = Teacher::s[i];
            }
        }

        return good ;
    }
};


int main() {

    Student s1, s2;

    s1.setName("Toan Nguyen Dinh");
    s1.setAge(32);
    s1.setToan(9);
    s1.setLy(9);
    s1.setHoa(8);

    Teacher t;

    t.setName("Thay Cong");
    t.setAge(30);
    t.setStudent(s1);


    s2.setName("Tom");
    s2.setAge(2);
    s2.setToan(9);
    s2.setLy(8);
    s2.setHoa(7);

    t.setStudent(s2);

    Student good = t.getGoodStudent();

    cout << "Good student is: " << good.getName() << ":" <<  good.TB();
    
    return 0;
}