,
Pan Peng
Creative Commons Attribution 3.0 Unported license
We give a fully dynamic (Las-Vegas style) algorithm with constant expected amortized time per update that maintains a proper (Δ+1)-vertex coloring of a graph with maximum degree at most Δ. This improves upon the previous O(log Δ)-time algorithm by Bhattacharya et al. (SODA 2018). Our algorithm uses an approach based on assigning random ranks to vertices and does not need to maintain a hierarchical graph decomposition. We show that our result does not only have optimal running time, but is also optimal in the sense that already deciding whether a Δ-coloring exists in a dynamically changing graph with maximum degree at most Δ takes Ω(log n) time per operation.
@InProceedings{henzinger_et_al:LIPIcs.STACS.2020.53,
author = {Henzinger, Monika and Peng, Pan},
title = {{Constant-Time Dynamic (\Delta+1)-Coloring}},
booktitle = {37th International Symposium on Theoretical Aspects of Computer Science (STACS 2020)},
pages = {53:1--53:18},
series = {Leibniz International Proceedings in Informatics (LIPIcs)},
ISBN = {978-3-95977-140-5},
ISSN = {1868-8969},
year = {2020},
volume = {154},
editor = {Paul, Christophe and Bl\"{a}ser, Markus},
publisher = {Schloss Dagstuhl -- Leibniz-Zentrum f{\"u}r Informatik},
address = {Dagstuhl, Germany},
URL = {https://drops.dagstuhl.de/entities/document/10.4230/LIPIcs.STACS.2020.53},
URN = {urn:nbn:de:0030-drops-119145},
doi = {10.4230/LIPIcs.STACS.2020.53},
annote = {Keywords: Dynamic graph algorithms, Graph coloring, Random sampling}
}