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.ISAAC.2019.45
URN: urn:nbn:de:0030-drops-115415
URL: http://dagstuhl.sunsite.rwth-aachen.de/volltexte/2019/11541/
He, Meng ;
Kazi, Serikzhan
Path and Ancestor Queries over Trees with Multidimensional Weight Vectors
Abstract
We consider an ordinal tree T on n nodes, with each node assigned a d-dimensional weight vector w in {1,2,...,n}^d, where d in N is a constant. We study path queries as generalizations of well-known {orthogonal range queries}, with one of the dimensions being tree topology rather than a linear order. Since in our definitions d only represents the number of dimensions of the weight vector without taking the tree topology into account, a path query in a tree with d-dimensional weight vectors generalize the corresponding (d+1)-dimensional orthogonal range query. We solve {ancestor dominance reporting} problem as a direct generalization of dominance reporting problem, in time O(lg^{d-1}{n}+k) and space of O(n lg^{d-2}n) words, where k is the size of the output, for d >= 2. We also achieve a tradeoff of O(n lg^{d-2+epsilon}{n}) words of space, with query time of O((lg^{d-1} n)/(lg lg n)^{d-2}+k), for the same problem, when d >= 3. We solve {path successor problem} in O(n lg^{d-1}{n}) words of space and time O(lg^{d-1+epsilon}{n}) for d >= 1 and an arbitrary constant epsilon > 0. We propose a solution to {path counting problem}, with O(n(lg{n}/lg lg{n})^{d-1}) words of space and O((lg{n}/lg lg{n})^{d}) query time, for d >= 1. Finally, we solve {path reporting problem} in O(n lg^{d-1+epsilon}{n}) words of space and O((lg^{d-1}{n})/(lg lg{n})^{d-2}+k) query time, for d >= 2. These results match or nearly match the best tradeoffs of the respective range queries. We are also the first to solve path successor even for d = 1.
BibTeX - Entry
@InProceedings{he_et_al:LIPIcs:2019:11541,
author = {Meng He and Serikzhan Kazi},
title = {{Path and Ancestor Queries over Trees with Multidimensional Weight Vectors}},
booktitle = {30th International Symposium on Algorithms and Computation (ISAAC 2019)},
pages = {45:1--45:17},
series = {Leibniz International Proceedings in Informatics (LIPIcs)},
ISBN = {978-3-95977-130-6},
ISSN = {1868-8969},
year = {2019},
volume = {149},
editor = {Pinyan Lu and Guochuan Zhang},
publisher = {Schloss Dagstuhl--Leibniz-Zentrum fuer Informatik},
address = {Dagstuhl, Germany},
URL = {https://drops.dagstuhl.de/opus/volltexte/2019/11541},
URN = {urn:nbn:de:0030-drops-115415},
doi = {10.4230/LIPIcs.ISAAC.2019.45},
annote = {Keywords: path queries, range queries, algorithms, data structures, theory}
}
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Keywords: |
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path queries, range queries, algorithms, data structures, theory |
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Collection: |
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30th International Symposium on Algorithms and Computation (ISAAC 2019) |
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Issue Date: |
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2019 |
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Date of publication: |
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28.11.2019 |
