@foxyshadis said:You do have to watch out for classes where things like "count" are implemented by walking the whole goddam class, like the linked lists they have you make in school. (A paradigm some students unfortunately take to heart.) Might waste a whole 4 bytes, can't have that.I assume that you're talking about having a counter in the list that would be updated as you insert and remove stuff from it.The problem with this is that while it turns counting elements into a constant operation instead of a linear one, it also prevent to implement other useful linked list operations (like spliting the list, extracting a sublist, etc.) in O(1).That's why the STL list, for instance, doesn't have a counter. It's easier to make your own subclass and the counter if you need it if you don't care about splitting, than the other way around.