cpp-set

std::set<int> myset;
myset.insert(100);
myset.insert(200);
myset.clear();

if (myset.count(i) != 0)
	std::cout << " is an element of myset.\n";
else
	std::cout << " is not an element of myset.\n";

{ // cbegin/cend(c++11): Returns a const_iterator pointing to the first element in the container/
	// Returns a const_iterator pointing to the past-the-end element in the container
	std::set<int> myset = { 50, 20, 60, 10, 25 };

	std::cout << "myset contains:";
	for (auto it = myset.cbegin(); it != myset.cend(); ++it)
		std::cout << ' ' << *it;

	std::cout << '\n';
}

{ // crbegin/crend(c++11):Return const_reverse_iterator to reverse beginning/
	// Return const_reverse_iterator to reverse end
	std::set<int> myset = { 50, 20, 60, 10, 25 };

	std::cout << "myset backwards:";
	for (auto rit = myset.crbegin(); rit != myset.crend(); ++rit)
		std::cout << ' ' << *rit;

	std::cout << '\n';
}