---
res:
bibo_abstract:
- We consider data-structures for answering reachability and distance queries on
constant-treewidth graphs with n nodes, on the standard RAM computational model
with wordsize W=Theta(log n). Our first contribution is a data-structure that
after O(n) preprocessing time, allows (1) pair reachability queries in O(1) time;
and (2) single-source reachability queries in O(n/log n) time. This is (asymptotically)
optimal and is faster than DFS/BFS when answering more than a constant number
of single-source queries. The data-structure uses at all times O(n) space. Our
second contribution is a space-time tradeoff data-structure for distance queries.
For any epsilon in [1/2,1], we provide a data-structure with polynomial preprocessing
time that allows pair queries in O(n^{1-\epsilon} alpha(n)) time, where alpha
is the inverse of the Ackermann function, and at all times uses O(n^epsilon) space.
The input graph G is not considered in the space complexity. @eng
bibo_authorlist:
- foaf_Person:
foaf_givenName: Krishnendu
foaf_name: Chatterjee, Krishnendu
foaf_surname: Chatterjee
foaf_workInfoHomepage: http://www.librecat.org/personId=2E5DCA20-F248-11E8-B48F-1D18A9856A87
orcid: 0000-0002-4561-241X
- foaf_Person:
foaf_givenName: Rasmus
foaf_name: Ibsen-Jensen, Rasmus
foaf_surname: Ibsen-Jensen
foaf_workInfoHomepage: http://www.librecat.org/personId=3B699956-F248-11E8-B48F-1D18A9856A87
orcid: 0000-0003-4783-0389
- foaf_Person:
foaf_givenName: Andreas
foaf_name: Pavlogiannis, Andreas
foaf_surname: Pavlogiannis
foaf_workInfoHomepage: http://www.librecat.org/personId=49704004-F248-11E8-B48F-1D18A9856A87
orcid: 0000-0002-8943-0722
bibo_doi: 10.4230/LIPIcs.ESA.2016.28
bibo_volume: 57
dct_date: 2016^xs_gYear
dct_language: eng
dct_publisher: Schloss Dagstuhl- Leibniz-Zentrum fur Informatik@
dct_title: Optimal reachability and a space time tradeoff for distance queries in
constant treewidth graphs@
...