C - Possible to create a tree level by level?

I'm studying trees right now, and I'd like to find some examples of how to create a binary(or k-ary) tree one level at a time, since I can't find it anywhere and my brain isn't working.

Anyone have any input on this? C's lack of functions doesn't help either. Thanks ahead, /prog/

>>7
For a breadth-first search I need a complete tree. My goal was avoiding the complete tree building part, which would be more efficient in my case. Xarn's post doesn't help me with this either, I already know how to build the complete tree and do a breadth-first search.