Small Stretch Spanners on Dynamic Graphs
نویسندگان
چکیده
We present fully dynamic algorithms for maintaining 3and 5-spanners of undirected graphs under a sequence of update operations. For unweighted graphs we maintain a 3or 5-spanner under insertions and deletions of edges; each operation is performed in O(n) amortized time over a sequence of Ω(n) updates. The maintained 3-spanner (resp., 5-spanner) has O(n) edges (resp., O(n) edges), which is known to be optimal. On weighted graphs with d different edge cost values, we maintain a 3or 5-spanner in O(n) amortized time over a sequence of Ω(d · n) updates. The maintained 3-spanner (resp., 5-spanner) has O(d · n) edges (resp., O(d · n) edges). The same approach can be extended to graphs with realvalued edge costs in the range [1, C]. All our algorithms are deterministic and are substantially faster than recomputing a spanner from scratch after each update.
منابع مشابه
Dynamic Algorithms for Graph Spanners
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