chickadee » disjoint-set » disjoint-set-unite!

disjoint-set-unite! ds xi yiprocedure

Unites the subsets that xi and yi belong to in ds.

This procedure may mutate ds if it's not already at its optimal state, and (not (= xi yi)).

It is an error if (> xi nelems) or (> yi nelems), with nelems the number of elements of the Universe set of ds.