HowTo sort std::map?

Question

Here is my map:

typedef std::map PortfolioMonth;

where PositionMonth is a structure,

Answer 1

Maybe the example code in the cplusplus.com artile on std::map constructor give the clarification you are looking for!

EDIT: The fifth map instantiated in the example code in the link above shows you how to change the comparator object.

Answer 2

There are several options gamedev.net. Look down the thread for the posting by Fruny.

Aside: Why would you not consider Boost as a possible solution provider? It's a respected, peer evaluated, well documented solution for professional C++ coders.