Hello everybody!

Is there a predefined data structure in C++ that allows you to insert numbers (maybe even dublicate keys) and effectively count the amount of numbers greater or less than a given value?

Now I'm using a recursive implementation of Red Black Tree — Here in original (Java) and Here translated to C++ with count_greater implemented.

One idea would be using std::lower_bound in std::map and then std::distance from map.begin() to the result iterator.