Succinct Dictionary Matching with No Slowdown
Succinct Dictionary Matching with No Slowdown
复制标题
简洁的字典匹配，不拖慢速度
DOI：
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发表时间：
2010
期刊：
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通讯作者：
Djamal Belazzougui
中科院分区：
文献类型：
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作者：
Djamal Belazzougui
字典匹配的问题是字符串匹配中的一个经典问题：给定（不必要常数）大小σ的字母的一组d字符串，构建数据结构，以便我们可以在任何文本中匹配T属于S的字符串的所有出现都是此问题的经典解决方案是Aho-Corasick Automaton，它使用占O（M log o（m log m）空间位，其中m≤n + 1是本文中的状态数。 log（n/d））空间位，同时仍保持在O（| t |+ OCC）时间中回答查询的能力。 （nlogσ）空间的位时，回答查询o（| t | log log n+occ）时间。如果在任何常数的0 <e <1中，则出现在集合s的Trie表示中的字符的经验熵。查询时间保持不变。
The problem of dictionary matching is a classical problem in string matching: given a set S of d strings of total length n characters over an (not necessarily constant) alphabet of size σ, build a data structure so that we can match in a any text T all occurrences of strings belonging to S. The classical solution for this problem is the Aho-Corasick automaton which finds all occ occurrences in a text T in time O(|T| + occ) using a representation that occupies O(m log m) bits of space where m ≤ n + 1 is the number of states in the automaton. In this paper we show that the Aho-Corasick automaton can be represented in just m(log σ + O(1)) + O(d log(n/d)) bits of space while still maintaining the ability to answer to queries in O(|T|+ occ) time. To the best of our knowledge, the currently fastest succinct data structure for the dictionary matching problem uses O(n log σ) bits of space while answering queries in O(|T| log log n + occ) time. In the paper we also show how the space occupancy can be reduced to m(H0+O(1))+O(d log(n/d)) where H0 is the empirical entropy of the characters appearing in the trie representation of the set S, provided that σ < me for any constant 0 < e < 1. The query time remains unchanged.