#include <memory>
#include <iostream>

int main()
{
	std::default_delete<int> d;
	std::unique_ptr<int> u1;
	std::cout << "u1: " << (u1 ? "not null" : "null") << '\n';

	std::unique_ptr<int> u2(nullptr);
	std::cout << "u2: " << (u2 ? "not null" : "null") << '\n';

	std::unique_ptr<int> u3(new int);
	std::cout << "u3: " << (u3 ? "not null" : "null") << '\n';

	std::unique_ptr<int> u4(new int, d);
	std::cout << "u4: " << (u4 ? "not null" : "null") << '\n';

	std::unique_ptr<int> u5(new int, std::default_delete<int>());
	std::cout << "u5: " << (u5 ? "not null" : "null") << '\n';

	std::unique_ptr<int> u6(std::move(u5));
	std::cout << "u6: " << (u6 ? "not null" : "null") << '\n';

	std::unique_ptr<int> u7(std::move(u6));
	std::cout << "u7: " << (u7 ? "not null" : "null") << '\n';
}