Optimal parallel pattern matching in strings

Pattern Matching in Strings

Unique Pattern Matching in Strings

Regular expression patterns are a key feature of document processing languages like Perl and XDuce. It is in this context that the first and longest match policies have been proposed to disambiguate the pattern matching process. We formally define a matching semantics with these policies and show that the generally accepted method of simulating longest match by first match and recursion is inco...

Fast Pattern Matching in Strings

An algorithm is presented which finds all occurrences of one. given string within another, in running time proportional to the sum of the lengths of the strings. The constant of proportionality is low enough to make this algorithm of practical use, and the procedure can also be extended to deal with some more general pattern-matching problems. A theoretical application of the algorithm shows th...

Abelian pattern matching in strings

Abelian pattern matching is a new class of pattern matching problems. In abelian patterns, the order of the characters in the substrings does not matter, e.g. the strings abbc and babc represent the same abelian pattern a+2b+c. Therefore, unlike classical pattern matching, we do not look for an exact (ordered) occurrence of a substring, rather the aim here is to find any permutation of a given ...

Algorithms for Jumbled Pattern Matching in Strings

The Parikh vector p(s) of a string s over a finite ordered alphabet Σ = {a1, . . . , aσ} is defined as the vector of multiplicities of the characters, p(s) = (p1, . . . , pσ), where pi = |{j | sj = ai}|. Parikh vector q occurs in s if s has a substring t with p(t) = q. The problem of searching for a query q in a text s of length n can be solved simply and worst-case optimally with a sliding win...