Question

I have a data structure and have to perform lookup on it, I would like to optimize things…

struct Data
{
 std::string id_;
 double data_;
};

I use currently a std::vector<Data> and std::find algorithm but I’m wondering if another data structure would be more convenient :

• hash table ?
• map ?
• boost multi index container ?
• other things ?

EDIT:

Each time I receive a message from network I have to lookup into this vector (with id as key), and update/retrieve some informations. (Data structure have more fields than in my example)

EDIT2:

• I don’t care about order.
• I have to insert/erase element into this data structure frequently.

Answer 1

It really depends on your requirements, but two possibilities are to sort your vector and do a binary search, or to use a map. Both can be implemented within about 15 minutes, so I suggest you try both of them.

Edit: Given your requirement that you want to add and remove things often, and the size of your data, I’d use an unordered_map (i.e. a hash table) as the first try. You can always change to another container later.