Algorithmic trade-offs for girth approximation in undirected graphs
Algorithmic trade-offs for girth approximation in undirected graphs
复制标题
无向图中周长近似的算法权衡
DOI:
10.1137/1.9781611977073.62
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发表时间:
2022
期刊:
影响因子:
--
通讯作者:
Zwick, Uri
中科院分区:
文献类型:
--
作者:
Kadria, Avi;Roditty, Liam;Sidford, Aaron;Williams, Virginia Vassilevska;Zwick, Uri
We present several new efficient algorithms for approximating the girth,g, of weighted and unweightedn-vertex,m-edge undirected graphs. For undirected graphs with polynomially bounded, integer, non-negative edge weights, we provide an algorithm that for every integerk≥ 1, runs inÕ(m+n1 + 1/klogg) time and returns a cycle of length at most 2kg. For unweighted, undirected graphs we present an algorithm that for everyk≥ 1, runs inÕ(n1 + 1/k) time and returns a cycle of length at most 2k[g/2], an almostk-approximation. Both algorithms provide trade-offs between the running time and the quality of the approximation. We also obtain faster algorithms for approximation factors better than 2, and improved approximations when the girth is odd or small (e.g., 3 and 4).