I need an equivalent to c++'s std::multimap<K, V, Comp, Alloc> in C-sharp. Does it exist in the standard library?
std::multimap<K, V, Comp, Alloc>
you can find a c# multimap collection @ http://code.google.com/p/self-balancing-avl-tree/ . it's based on a self balancing avl tree which is also included with the code.