Does the C++ standard library have an “ordered set” datastructure? By ordered set, I mean something that is exactly the same as the ordinary std::set but that remembers the order in which you added the items to it.
If not, what is the best way to simulate one? I know you could do something like have a set of pairs with each pair storing the number it was added in and the actual value, but I dont want to jump through hoops if there is a simpler solution.
No single, homogeneous data structure will have this property, since it is either sequential (i.e. elements are arranged in insertion order) or associative (elements are arranged in some order depending on value).
The best, clean approach would perhaps be something like Boost.MultiIndex, which allows you to add multiple indexes, or “views”, on a container, so you can have a sequential and an ordered index.