Pattern Matching in Trace Monoids
نویسنده
چکیده
An algorithm is presented solving the factor problem in trace monoids Given two traces represented by words the algorithm determines in linear time whether the rst trace is a factor of the second one The space used for this task is linear in the length of the rst word Similar to the Knuth Morris Pratt Algorithm for the factor problem on words the algorithm simulates a nite automaton determined by the rst word on the second word To develop the algorithm we examine overlaps of two traces and show that they form a lattice Finally we investigate the lattice of extensible trace pairs which represent still extensible pre xes of a searched factor appearing in some other trace because of their close relations to the structures used by the algorithm
منابع مشابه
Inclusion Problems in Trace Monoids
We suggest a number efficient pattern matching algorithms for dependence graphs of traces. A graph G = (V, E, λ) of partial order labeled by letters from alphabet Σ belongs to this class iff there exists a reflexive and symmetric relation D ⊂ Σ × Σ such that if v <G v′ and (λ(v).λ(v′)) ∈ D → (v, v′) ∈ E. We consider pattern matching problems related to problems of recognizing frequent patterns ...
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