]> Bonjour, > Is it just a coincidence that the numerous varieties of balanced > tree (AVL, 2-3-4, red-black, ...) all seem to be non-canonical? Or > is it essential to their efficiency? (Perhaps this is a question for > another forum.) It is not a coincidence. I remember having read somewhere that it could be proven that if a balanced tree (based on comparisons) did not have enough different representations of a same set, then the insertion could not be done in logarithmic time. Diego Olivier ------------------- To unsubscribe, mail caml-list-request@inria.fr Archives: http://caml.inria.fr Bug reports: http://caml.inria.fr/bin/caml-bugs FAQ: http://caml.inria.fr/FAQ/ Beginner's list: http://groups.yahoo.com/group/ocaml_beginners