arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 1605.04491cs.DS
收藏

通过树划分改进的距离敏感性预言机

Improved distance sensitivity oracles via tree partitioning

Ran Duan, Tianyi Zhang

摘要:

提出了一种改进的距离灵敏度预言机(DSO)结构。该任务是对一个非负权图进行预处理,使得一个数据结构可以快速地为每个三元组的源、终端和故障顶点回答替换路径长度。先前的最佳算法在时间上构造$\tilde{O}(mn)$,其在$O(1)$时间上处理查询的大小为$O(n^2\log n)$的距离敏感性预言机。作为改进,我们的oracle占用$O(n^2)$空间,同时保留$O(1)$查询效率和$\tilde{O}(mn)$预处理时间。值得注意的是,我们的新数据结构的空间复杂度和查询时间是渐近最优的。

英文摘要:

We introduce an improved structure of distance sensitivity oracle (DSO). The task is to pre-process a non-negatively weighted graph so that a data structure can quickly answer replacement path length for every triple of source, terminal and failed vertex. The previous best algorithm constructs in time $\tilde{O}(mn)$ a distance sensitivity oracle of size $O(n^2\log n)$ that processes queries in $O(1)$ time. As an improvement, our oracle takes up $O(n^2)$ space, while preserving $O(1)$ query efficiency and $\tilde{O}(mn)$ preprocessing time. One should notice that space complexity and query time of our novel data structure are asymptotically optimal.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

↑