License: Creative Commons Attribution 3.0 Unported license (CC BY 3.0)
When quoting this document, please refer to the following
DOI: 10.4230/LIPIcs.SoCG.2018.5
URN: urn:nbn:de:0030-drops-87182
URL: http://dagstuhl.sunsite.rwth-aachen.de/volltexte/2018/8718/
Go to the corresponding LIPIcs Volume Portal


Ashida, Ryo ; Nakagawa, Kotaro

O~(n^{1/3})-Space Algorithm for the Grid Graph Reachability Problem

pdf-format:
LIPIcs-SoCG-2018-5.pdf (0.6 MB)


Abstract

The directed graph reachability problem takes as input an n-vertex directed graph G=(V,E), and two distinguished vertices s and t. The problem is to determine whether there exists a path from s to t in G. This is a canonical complete problem for class NL. Asano et al. proposed an O~(sqrt{n}) space and polynomial time algorithm for the directed grid and planar graph reachability problem. The main result of this paper is to show that the directed graph reachability problem restricted to grid graphs can be solved in polynomial time using only O~(n^{1/3}) space.

BibTeX - Entry

@InProceedings{ashida_et_al:LIPIcs:2018:8718,
  author =	{Ryo Ashida and Kotaro Nakagawa},
  title =	{{O~(n^{1/3})-Space Algorithm for the Grid Graph Reachability Problem}},
  booktitle =	{34th International Symposium on Computational Geometry (SoCG 2018)},
  pages =	{5:1--5:13},
  series =	{Leibniz International Proceedings in Informatics (LIPIcs)},
  ISBN =	{978-3-95977-066-8},
  ISSN =	{1868-8969},
  year =	{2018},
  volume =	{99},
  editor =	{Bettina Speckmann and Csaba D. T{\'o}th},
  publisher =	{Schloss Dagstuhl--Leibniz-Zentrum fuer Informatik},
  address =	{Dagstuhl, Germany},
  URL =		{http://drops.dagstuhl.de/opus/volltexte/2018/8718},
  URN =		{urn:nbn:de:0030-drops-87182},
  doi =		{10.4230/LIPIcs.SoCG.2018.5},
  annote =	{Keywords: graph reachability, grid graph, graph algorithm, sublinear space algorithm}
}

Keywords: graph reachability, grid graph, graph algorithm, sublinear space algorithm
Collection: 34th International Symposium on Computational Geometry (SoCG 2018)
Issue Date: 2018
Date of publication: 08.06.2018


DROPS-Home | Fulltext Search | Imprint | Privacy Published by LZI