LEA
Fakultät für Informatik der Technischen Universität München
Lehrstuhl für Effiziente Algorithmen
Postadresse: 80290 München; Hausadresse: Arcisstr.21, 80333 München

RNC-Approximation Algorithms for the Steiner problem

Hans-Jürgen Prömel and Angelika Steger


In this paper we present an RNC-algorithm for finding a minimum spanning tree in a weighted 3-uniform hypergraph, assuming the edge weights are given in unary, and a fully polynomial time randomized approximation scheme if the edge weights are given in binary. From this result we then derive RNC-approximation algorithms for the Steiner problem in networks with approximation ratio (1+e)5/3 for all e>0.