C - How to implement Set data structure?

Question

Is there any tricky way to implement a set data structure (a collection of unique values) in C? All elements in a set will be of the same type and there is a huge RAM memory

Answer 1

Sets are usually implemented as some variety of a binary tree. Red black trees have good worst case performance.

These can also be used to build an map to allow key / value lookups.

This approach requires some sort of ordering on the elements of the set and the key values in a map.

I'm not sure how you would manage a set that could possibly contain itself using binary trees if you limit set membership to well defined types in C ... comparison between such constructs could be problematic. You could do it easily enough in C++, though.