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| Content Provider | Springer Nature Link |
|---|---|
| Author | Porat, Ely Roditty, Liam |
| Copyright Year | 2013 |
| Abstract | Thorup and Zwick (J. ACM 52(1):1–24, 2005 and STOC’01) in their seminal work introduced the notion of distance oracles. Given an n-vertex weighted undirected graph with m edges, they show that for any integer k≥1 it is possible to preprocess the graph in $\tilde {O}(mn^{1/k})$ time and generate a compact data structure of size O(kn 1+1/k ). For each pair of vertices, it is then possible to retrieve an estimated distance with multiplicative stretch 2k−1 in O(k) time. For k=2 this gives an oracle of O(n 1.5) size that produces in constant time estimated distances with stretch 3. Recently, Pǎtraşcu and Roditty (In: Proc. of 51st FOCS, 2010) broke the theoretical status-quo in the field of distance oracles and obtained a distance oracle for sparse unweighted graphs of O(n 5/3) size that produces in constant time estimated distances with stretch 2.In this paper we show that it is possible to break the stretch 2 barrier at the price of non-constant query time in unweighted undirected graphs. We present a data structure that produces estimated distances with 1+ε stretch. The size of the data structure is O(nm 1−ε′) and the query time is $\tilde {O}(m^{1-\varepsilon '})$ . Using it for sparse unweighted graphs we can get a data structure of size O(n 1.87) that can supply in O(n 0.87) time estimated distances with multiplicative stretch 1.75. |
| Starting Page | 516 |
| Ending Page | 528 |
| Page Count | 13 |
| File Format | |
| ISSN | 01784617 |
| Journal | Algorithmica |
| Volume Number | 67 |
| Issue Number | 4 |
| e-ISSN | 14320541 |
| Language | English |
| Publisher | Springer US |
| Publisher Date | 2013-08-28 |
| Publisher Place | Boston |
| Access Restriction | One Nation One Subscription (ONOS) |
| Subject Keyword | Graph algorithms Distance oracles Data structures Algorithm Analysis and Problem Complexity Theory of Computation Mathematics of Computing Algorithms Computer Systems Organization and Communication Networks Data Structures, Cryptology and Information Theory |
| Content Type | Text |
| Resource Type | Article |
| Subject | Applied Mathematics Computer Science Applications |
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