Optimal parallel randomized algorithms for three-dimensional convex hulls and related problems

TLDR: This paper presents an optimal parallel randomized algorithm for computing intersection of half spaces in three dimensions that is randomized in the sense that they use a total of only polylogarithmic number of random bits and terminate in the claimed time bound with probability of 1 - n - \alpha for any fixed $\alpha > 0$.

Abstract: Further applications of random sampling techniques which have been used for deriving efficient parallel algorithms are presented by J. H. Reif and S. Sen [Proc. 16th International Conference on Parallel Processing, 1987]. This paper presents an optimal parallel randomized algorithm for computing intersection of half spaces in three dimensions. Because of well-known reductions, these methods also yield equally efficient algorithms for fundamental problems like the convex hull in three dimensions, Voronoi diagram of point sites on a plane, and Euclidean minimal spanning tree. The algorithms run in time $T = O(\log n)$ for worst-case inputs and use $P = O(n)$ processors in a CREW PRAM model where n is the input size. They are randomized in the sense that they use a total of only polylogarithmic number of random bits and terminate in the claimed time bound with probability $1 - n^{ - \alpha } $ for any fixed $\alpha > 0$. They are also optimal in $P\cdot T$ product since the sequential time bound for all thes...