#include "iostream"
#include "string"
#include "vector"
#include <numeric>

class University;
class UniMember {
public:
    University* uni;
    std::string name;
    int id;

    UniMember(University* university, std::string name, int id) {
        this->uni = university;
        this->name = name;
        this->id = id;
    }
};

class UniWorker: public UniMember {
public:
    UniWorker(University* university, std::string name, int id)
            : UniMember(university, name, id) {}

};

class UniStudent: public UniMember {
public:
    UniStudent(University* university, std::string name, int id)
        : UniMember(university, name, id) {}

    void evaluate_exam(double grade){
        grades.push_back(grade);
    }

    double calc_avg(){
        if(grades.empty()) return 0;
        auto const count = static_cast<double>(grades.size());
        return std::reduce(grades.begin(), grades.end()) / count;
    }

private:
    std::vector <double> grades;
};

class University {
public:
    std::string name;
    UniWorker* dean;

    University(std::string name) {
        this->name = name;
    }

    UniWorker* create_worker(std::string mem_name) {
        int id = members.size() + 1;
        UniWorker* worker = new UniWorker(this, mem_name, id);
        members.push_back(worker);
        return worker;
    }

    UniStudent* create_student(std::string mem_name) {
        int id = members.size() + 1;
        UniStudent* student = new UniStudent(this, mem_name, id);
        members.push_back(student);
        return student;
    }

    void elect_dean(UniWorker* worker) {
        dean = worker;
    }

    int count_members() {
        return members.size();
    }
private:
    std::vector <UniMember*> members;
};


int main() {
    University* trier = new University("Trier");
    UniWorker* dean = trier->create_worker("Eva Eckkrammer");
    trier->elect_dean(dean);
    UniStudent* student = trier->create_student("Jan-Niclas Loosen");
    student->evaluate_exam(1.3);
    student->evaluate_exam(2.3);
    student->evaluate_exam(1.3);
    student->evaluate_exam(3.3);

    std::cout << "Die Universitaet " << trier->name << " hat " << trier->count_members() << " Mitglieder." << std::endl;
    std::cout << "Die Dekanin der Universitaet " << trier->name << " heisst " << trier->dean->name << "." << std::endl;
    std::cout << student->name << " hat einen Notenschnitt von " << student->calc_avg() << "." << std::endl;
}