int main() {
    UniquePtr<int> a;
    int* t = new int;
    *t = 5;
    a.reset(t);
    UniquePtr<int> b(std::move(a));
    int *c = new int;
    *c = 1000;
    UniquePtr<int> z(std::move(c));
    std::cout << *z;
    z.swap(b);
    std::cout << *(z.release());
    return 0;
}