Multiset (top) -- order

Recently, we have seen boost: bimap <multiset_of <A>, multiset_of <B>, with_info <C> in the project code. Although I have used boost: bimap, it's just a simple application. This mulstiset_of made me feel a little confused.

I searched for multiset_of on the Internet and did not find much useful information. I read two articles about it, but I still don't know what it is. Later, I felt that I had never touched the concept of Multiset in mathematics, nor had I used Multiset in STL. If you have used STL Multiset, understanding the multiset_of in bimap may be much easier.

Leave several links first, and study after going home.

Mathematical Concepts of Multiset:

Http://en.wikipedia.org/wiki/Multiset

Multiset in STL:

Http://www.cplusplus.com/reference/set/multiset/

Http://blog.csdn.net/cumirror/article/details/5526485

Articles about boost: bimap: multiset_of:

Http://www.cnblogs.com/lin1270/archive/2011/01/12/1933908.html

Http://stackoverflow.com/questions/8441846/how-to-traverse-a-map-by-value