Online Construction of Subsequence Automata for Multiple Texts
نویسندگان
چکیده
We consider a deterministic finite automaton which accepts all subsequences of a set of texts, called subsequence automaton. We show an online algorithm for constructing subsequence automaton for a set of texts. It runs in O(|Σ|(m+ k) +N) time using O(|Σ|m) space, where |Σ| is the size of alphabet, m is the size of the resulting subsequence automaton, k is the number of texts, and N is the total length of texts. It can be used to preprocess a given set S of texts in such a way that for any query w ∈ Σ∗, returns in O(|w|) time the number of texts in S which contain w as a subsequence. We also show an upper bound of the size of automaton compared to the minimum automaton.
منابع مشابه
Online construction of subsequence automata for multiple texts by Hiromasa Hoshino , Ayumi Shinohara , Masayuki
We consider a deterministic finite automaton which accepts all subsequences of a set of texts, called subsequence automaton. We show an online algorithm for constructing subsequence automaton for a set of texts. It runs in O(|Σ|m) time using O(|Σ|m) space, where m is the number of states of the subsequence automaton, and |Σ| is the size of alphabet. For k texts of length n, since m = O(n), it r...
متن کاملOnline construction of subsequence automata for multiple texts by Hiromasa Hoshino
We consider a deterministic finite automaton which accepts all subsequences of a set of texts, called subsequence automaton. We show an online algorithm for constructing subsequence automaton for a set of texts. It runs in O(|Σ|(m + k) + N) time using O(|Σ|m) space, where |Σ| is the size of alphabet, m is the size of the resulting subsequence automaton, k is the number of texts, N is the total ...
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