Delaunay triangulation is available for any CCC system in the sense of Knuth's ``Axioms and Hulls''
The result of triangulation is an abstract value of type
Then one can iterate over all edges of the triangulation.
triangulate a computes the Delaunay triangulation of a set of
points, given as an array
N is the number of points
Array.length a), then the running time is $O(N \log N)$
on the average and $O(N^2)$ on the worst-case. The space used is