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arXiv · 1103.1109

Fully dynamic maximal matching in O(log n) update time

Surender Baswana·Manoj Gupta·Sandeep Sen
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Abstract

We present an algorithm for maintaining maximal matching in a graph under addition and deletion of edges. Our data structure is randomized that takes O(log n) expected amortized time for each edge update where n is the number of vertices in the graph. While there is a trivial O(n) algorithm for edge update, the previous best known result for this problem for a graph with n vertices and m edges is O({(n+ m)}^{0.7072})which is sub-linear only for a sparse graph. For the related problem of maximum matching, Onak and Rubinfield designed a randomized data structure that achieves O(log^2 n) amortized time for each update for maintaining a c-approximate maximum matching for some large constant c. In contrast, we can maintain a factor two approximate maximum matching in O(log n) expected time per update as a direct corollary of the maximal matching scheme. This in turn also implies a two approximate vertex cover maintenance scheme that takes O(log n) expected time per update.

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Surender Baswana, Manoj Gupta, Sandeep Sen. 2011-03-06. Fully dynamic maximal matching in O(log n) update time. https://arxiv.org/abs/1103.1109

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