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arXiv 1005.4652cs.DS
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动态字符串的简洁表示

Succinct Representations of Dynamic Strings

Meng He, J. Ian Munro

摘要:

从大小为$σ$的字母表中对长度为n的字符串进行排序和选择操作已广泛用于简洁数据结构的设计中。在许多应用程序中,字符串本身需要动态维护,允许插入和删除字符串中的字符。在字长为$w=Ω(\lg n)$的字RAM模型下,我们设计了一个简洁的动态字符串表示,使用$nH_0 + o(n)\lgσ+ O(w)$位来支持$O(\frac{\lg n}{\lg\lg n}(\frac{\lg σ}{\lg\lg n}+1))$时间内的排序、选择、插入和删除。当字母表大小小时,即当$σ= O(\polylog (n))$时,包括字符串是位向量的情况,在$O(\frac{\lg n}{\lg\lg n})$时间内支持这些操作。我们的数据结构是更有效的比以前的结果在同一个问题上,我们已经应用它们来提高结果的设计和建设的空间效率的文本索引。

英文摘要:

The rank and select operations over a string of length n from an alphabet of size $σ$ have been used widely in the design of succinct data structures. In many applications, the string itself need be maintained dynamically, allowing characters of the string to be inserted and deleted. Under the word RAM model with word size $w=Ω(\lg n)$, we design a succinct representation of dynamic strings using $nH_0 + o(n)\lgσ+ O(w)$ bits to support rank, select, insert and delete in $O(\frac{\lg n}{\lg\lg n}(\frac{\lg σ}{\lg\lg n}+1))$ time. When the alphabet size is small, i.e. when $σ= O(\polylog (n))$, including the case in which the string is a bit vector, these operations are supported in $O(\frac{\lg n}{\lg\lg n})$ time. Our data structures are more efficient than previous results on the same problem, and we have applied them to improve results on the design and construction of space-efficient text indexes.

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。

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