Better tradeoffs for exact distance oracles in planar graphs

Publikation: Bidrag til bog/antologi/rapportKonferencebidrag i proceedingsForskningfagfællebedømt

We present an O(n1:5)-space distance oracle for directed planar graphs that answers distance queries in O(log n) time. Our oracle both significantly simplifies and significantly improves the recent oracle of Cohen-Addad, Dahlgaard and Wulff-Nilsen [FOCS 2017], which uses O(n5=3)-space and answers queries in O(log n) time. We achieve this by designing an elegant and efficient point location data structure for Voronoi diagrams on planar graphs. We further show a smooth tradeoff between space and query-time. For any S 2 [n; n2], we show an oracle of size S that answers queries in ~O (maxf1; n1:5=Sg) time. This new tradeoff is currently the best (up to polylogarithmic factors) for the entire range of S and improves by polynomial factors over all previously known tradeoffs for the range S 2 [n; n5=3].

TitelProceedings of the Twenty-Ninth Annual ACM-SIAM Symposium on Discrete Algorithms
RedaktørerA. Czumaj
ForlagSociety for Industrial and Applied Mathematics
ISBN (Elektronisk)9781611975031
StatusUdgivet - 2018
Begivenhed29th Annual ACM-SIAM Symposium on Discrete Algorithms, SODA 2018 - New Orleans, USA
Varighed: 7 jan. 201810 jan. 2018


Konference29th Annual ACM-SIAM Symposium on Discrete Algorithms, SODA 2018
ByNew Orleans
SponsorACM Special Interest Group on Algorithms and Computation Theory (SIGACT), SIAM Activity Group on Discrete Mathematics

ID: 204040383