Sciweavers

STOC
2002
ACM

Improved decremental algorithms for maintaining transitive closure and all-pairs shortest paths

15 years 27 days ago
Improved decremental algorithms for maintaining transitive closure and all-pairs shortest paths
We present improved algorithms for maintaining transitive closure and all-pairs shortest paths/distances in a digraph under deletion of edges. For the problem of transitive closure, the previous best known algorithms, for achieving O(1) query time, require O(min(m, n3 m )) amortized update time, implying an upper bound of O(n 3 2 ) on update time per edge-deletion. We present an algorithm that achieves O(1) query time and O(n log2 n+ n2 m log n) update time per edge-deletion, thus improving the upper bound to O(n 4 3 3 log n). For the problem of maintaining all-pairs shortest distances in unweighted digraph under deletion of edges, we present an algorithm that requires O(n3 m log2 n) amortized update time and answers a distance query in O(1) time. This improves the previous best known update bound by a factor of log n. For maintaining all-pairs shortest paths, we present an algorithm that achieves O(min(n 3 2 log n, n3 m log2 n)) amortized update time and reports a shortest path i...
Surender Baswana, Ramesh Hariharan, Sandeep Sen
Added 03 Dec 2009
Updated 03 Dec 2009
Type Conference
Year 2002
Where STOC
Authors Surender Baswana, Ramesh Hariharan, Sandeep Sen
Comments (0)