int main() {
	{
		//Wrong
		set  s = {1,2,3,4,5};
		auto it = s.lower_bound(3);
		s.erase(it);
		it++;
		printf("%d\n", *it);
	} {
		//Correct 1
		set  s = {1,2,3,4,5};
		auto it = s.lower_bound(3);
		s.erase(it++);
		printf("%d\n", *it);
	} {
		//Correct 2
		set  s = {1,2,3,4,5};
		auto it = s.lower_bound(3);
		it = s.erase(it);
		printf("%d\n", *it);
	}
}