"chun ping wang" wrote in message news:7253f6b30609151541k12dbd55aw7740d1beb895eca5@mail.gmail.com... I have a question on unordered_map. Are there are any boost library containers that acts like an associative array but also have the items base on how the order their inserted in. I.E. first item inserted is first one, second one is second. Try http://www.boost.org/libs/multi_index/doc/index.html, I think it has what you need. Jeff Flinn