Drill 21: Key term — Inheritance and polymorphism

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

class Lesson {
public:
    virtual ~Lesson() = default;
    virtual std::string describe() const = 0;
};

class Video : public Lesson {
public:
    std::string describe() const override {
        return "video lesson";
    }
};

class Quiz : public Lesson {
public:
    std::string describe() const override {
        return "quiz lesson";
    }
};

int main() {
    std::vector<std::unique_ptr<Lesson>> lessons;
    lessons.push_back(std::make_unique<Video>());
    lessons.push_back(std::make_unique<Quiz>());

    for (const auto& lesson : lessons) {
        std::cout << lesson->describe() << "\n";
    }
}