Arc-Disjoint Paths in Expander Digraphs

  • Authors:
  • T. Bohman;A. Frieze

  • Affiliations:
  • -;-

  • Venue:
  • FOCS '01 Proceedings of the 42nd IEEE symposium on Foundations of Computer Science
  • Year:
  • 2001

Quantified Score

Hi-index 0.00

Visualization

Abstract

Given a digraph D = (V;A) and a set of k pairs of vertices in V , we are interested in finding for each pair (xi, yi), a directed path connecting xi to yi, such that the set of k paths so found is arc-disjoint. For arbitrary graphs the problem is NP-complete, even for k = 2.We present a polynomial time randomized algorithm for finding arc-disjoint paths in an r-regular expander digraph D We show that if D has sufficiently strong expansion propertiesand r is sufficiently large then all sets of k = \Omega (n/\log n) pairs of vertices can be joined. This is within a constant factor of best possible.