Abstract
We present a deterministic near-linear time algorithm that computes the edge-connectivity and finds a minimum cut for a simple undirected unweighted graph G with n vertices and m edges. This is the first o(mn) time deterministic algorithm for the problem. In near-linear time we can also construct the classic cactus representation of all minimum cuts. The previous fastest deterministic algorithm by Gabow from STOC'91 took Õ(m + λ2 n), where λ is the edge connectivity, but λ could be Ω(n). At STOC'96 Karger presented a randomized near linear time Monte Carlo algorithm for the minimum cut problem. As he points out, there is no better way of certifying the minimality of the returned cut than to use Gabow's slower deterministic algorithm and compare sizes. Our main technical contribution is a near-linear time algorithm that contracts vertex sets of a simple input graph G with minimum degree δ, producing a multigraph G¯ with Õ(m/δ) edges which preserves all minimum cuts of G with at least two vertices on each side. In our deterministic near-linear time algorithm, we will decompose the problem via low-conductance cuts found using PageRank a la Brin and Page (1998), as analyzed by Andersson, Chung, and Lang at FOCS'06. Normally such algorithms for low-conductance cuts are randomized Monte Carlo algorithms, because they rely on guessing a good start vertex. However, in our case, we have so much structure that no guessing is needed.
Original language | English |
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Title of host publication | Proceedings of the Forty-Seventh Annual ACM on Symposium on Theory of Computing : STOC '15 |
Number of pages | 10 |
Publisher | Association for Computing Machinery |
Publication date | 14 Jun 2015 |
Pages | 665-674 |
ISBN (Print) | 978-1-4503-3536-2 |
DOIs | |
Publication status | Published - 14 Jun 2015 |
Event | Annual ACM Symposium on the Theory of Computing 2015 - Portland, United States Duration: 15 Jun 2015 → 17 Jun 2015 Conference number: 47 |
Conference
Conference | Annual ACM Symposium on the Theory of Computing 2015 |
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Number | 47 |
Country/Territory | United States |
City | Portland |
Period | 15/06/2015 → 17/06/2015 |