arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 1206.6982cs.DS
收藏

最优动态序列表示

Optimal Dynamic Sequence Representations

Gonzalo Navarro, Yakov Nekrich

摘要:

我们描述了一个数据结构,支持访问,排名和选择查询,以及符号插入和删除,在字符串$S[1,n]$在字母表$[1..σ]$的时间$O(\lg n/\lg\lg n)$,这是最佳的,即使在二进制序列和摊销的意义。我们的时间是查询的最坏情况和更新的摊销。这种复杂性比以前最好的复杂性好一个$Θ(1+\lgσ/\lg\lg n)$因子。我们还设计了一个变体,其中时间是最坏情况,但排名和更新需要$O(\lg n)$时间。我们的结构使用$nH_0(S)+o(n\lgσ) + O(σ\lg n)$位,其中$H_0(S)$是$S$的零阶熵。最后,我们追求各种推广和应用的结果。

英文摘要:

We describe a data structure that supports access, rank and select queries, as well as symbol insertions and deletions, on a string $S[1,n]$ over alphabet $[1..σ]$ in time $O(\lg n/\lg\lg n)$, which is optimal even on binary sequences and in the amortized sense. Our time is worst-case for the queries and amortized for the updates. This complexity is better than the best previous ones by a $Θ(1+\lgσ/\lg\lg n)$ factor. We also design a variant where times are worst-case, yet rank and updates take $O(\lg n)$ time. Our structure uses $nH_0(S)+o(n\lgσ) + O(σ\lg n)$ bits, where $H_0(S)$ is the zero-order entropy of $S$. Finally, we pursue various extensions and applications of the result.

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。

↑