#include <iostream>
#include <utility>
#include <memory>

unsigned int counter = 1;

class Stuff {
    private:
        unsigned int y;

    public:
        Stuff(unsigned int x) {
            y = x * x;
        }
};

class A {
    public:
        int id;

        A() {
            id = counter++;

            ptr = std::make_unique<Stuff>(id);
        };

        std::unique_ptr<Stuff>& get_data() {
            return ptr;
        }

        A(A&& to_move) {
            id = to_move.id;

            ptr = std::move(to_move.get_data());
        }

    private:
        std::unique_ptr<Stuff> ptr;
};

A get_A() {
    return A();
}

int main() {
    A a;
    A b = std::move(a);
    A c = get_A();
    A d = std::move(get_A());

    std::cout << a.id << b.id << c.id << d.id << '\n';

    return 0;
}