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Related papers: Fast Algorithms for Exact String Matching

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String matching is one of the most fundamental problems in computer science. A natural problem is to determine the number of characters that need to be queried (i.e. the decision tree complexity) in a string in order to decide whether this…

Computational Complexity · Computer Science 2018-06-29 Xiaoyu He , Neng Huang , Xiaoming Sun

The equidistant subsequence pattern matching problem is considered. Given a pattern string $P$ and a text string $T$, we say that $P$ is an \emph{equidistant subsequence} of $T$ if $P$ is a subsequence of the text such that consecutive…

Data Structures and Algorithms · Computer Science 2020-02-18 Mitsuru Funakoshi , Yuto Nakashima , Shunsuke Inenaga , Hideo Bannai , Masayuki Takeda , Ayumi Shinohara

More than 120 algorithms have been developed for exact string matching within the last 40 years. We show by experiments that the \naive{} algorithm exploiting SIMD instructions of modern CPUs (with symbols compared in a special order) is…

Data Structures and Algorithms · Computer Science 2016-12-06 Jorma Tarhio , Jan Holub , Emanuele Giaquinta

With the advent of large-scale heterogeneous search engines comes the problem of unified search control resulting in mismatches that could have otherwise avoided. A mechanism is needed to determine exact patterns in web mining and…

Cryptography and Security · Computer Science 2019-01-28 Nazim Uddin Sheikh , Hasina Rahman , Hamid Al-Qahtani

We revisit the complexity of approximate pattern matching in an elastic-degenerate string. Such a string is a sequence of $n$ finite sets of strings of total length $N$, and compactly describes a collection of strings obtained by first…

Data Structures and Algorithms · Computer Science 2025-03-04 Paweł Gawrychowski , Adam Górkiewicz , Pola Marciniak , Solon P. Pissis , Karol Pokorski

We consider the problem of computing the Maximal Exact Matches (MEMs) of a given pattern $P[1 .. m]$ on a large repetitive text collection $T[1 .. n]$, which is represented as a (hopefully much smaller) run-length context-free grammar of…

Data Structures and Algorithms · Computer Science 2023-09-06 Gonzalo Navarro

Two strings are considered to have parameterized matching when there exists a bijection of the parameterized alphabet onto itself such that it transforms one string to another. Parameterized matching has application in software duplication…

Data Structures and Algorithms · Computer Science 2024-12-03 Apurba Saha , Iftekhar Hakim Kaowsar , Mahdi Hasnat Siyam , M. Sohel Rahman

In this paper we are interested in indexing texts for substring matching queries with one edit error. That is, given a text $T$ of $n$ characters over an alphabet of size $\sigma$, we are asked to build a data structure that answers the…

Data Structures and Algorithms · Computer Science 2014-08-25 Djamal Belazzougui

Given two strings $S$ and $P$, the Episode Matching problem is to find the shortest substring of $S$ that contains $P$ as a subsequence. The best known upper bound for this problem is $\tilde O(nm)$ by Das et al. (1997) , where $n,m$ are…

Data Structures and Algorithms · Computer Science 2024-02-15 Philip Bille , Inge Li Gørtz , Shay Mozes , Teresa Anna Steiner , Oren Weimann

In this work, we tackle a natural variation of the String Matching Problem on the case of a dynamic pattern, that is, given a static text $T$ and a pattern $P$, we want to support character additions and deletions to the pattern, and after…

Data Structures and Algorithms · Computer Science 2025-06-16 Bruno Monteiro , Vinicius dos Santos

Strings in the real world are often encoded with some level of uncertainty. In the character-level uncertainty model, an uncertain string $X$ of length $n$ on an alphabet $\Sigma$ is a sequence of $n$ probability distributions over…

Data Structures and Algorithms · Computer Science 2024-03-22 Esteban Gabory , Chang Liu , Grigorios Loukides , Solon P. Pissis , Wiktor Zuba

The problem of finding factors of a text string which are identical or similar to a given pattern string is a central problem in computer science. A generalised version of this problem consists in implementing an index over the text to…

Data Structures and Algorithms · Computer Science 2016-02-04 Carl Barton , Tomasz Kociumaka , Solon P. Pissis , Jakub Radoszewski

The algorithmic tasks of computing the Hamming distance between a given pattern of length $m$ and each location in a text of length $n$ is one of the most fundamental algorithmic tasks in string algorithms. Unfortunately, there is evidence…

Data Structures and Algorithms · Computer Science 2015-12-15 Tsvi Kopelowitz , Ely Porat

We present an online algorithm to deal with pattern matching in strings. The problem we investigate is commonly known as string matching with mismatches in which the objective is to report the number of characters that match when a pattern…

Data Structures and Algorithms · Computer Science 2016-03-11 Vinodprasad P

Searching for all occurrences of a pattern in a text is a fundamental problem in computer science with applications in many other fields, like natural language processing, information retrieval and computational biology. Sampled string…

Data Structures and Algorithms · Computer Science 2019-08-19 Simone Faro , Arianna Pavone , Francesco Pio Marino

We introduce a novel definition of approximate palindromes in strings, and provide an algorithm to find all maximal approximate palindromes in a string with up to $k$ errors. Our definition is based on the usual edit operations of…

Data Structures and Algorithms · Computer Science 2007-05-23 A. H. L. Porto , V. C. Barbosa

Cartesian tree pattern matching consists of finding all the factors of a text that have the same Cartesian tree than a given pattern. There already exist theoretical and practical solutions for the exact case. In this paper, we propose the…

Data Structures and Algorithms · Computer Science 2025-05-15 Bastien Auvray , Julien David , Samah Ghazawi , Richard Groult , Gad M. Landau , Thierry Lecroq

A family of comparison-based exact pattern matching algorithms is described. They utilize multi-dimensional arrays in order to process more than one adjacent text window in each iteration of the search cycle. This approach leads to a lower…

Data Structures and Algorithms · Computer Science 2016-08-31 Igor O. Zavadskyi

We study the classic Text-to-Pattern Hamming Distances problem: given a pattern $P$ of length $m$ and a text $T$ of length $n$, both over a polynomial-size alphabet, compute the Hamming distance between $P$ and $T[i\, .\, . \, i+m-1]$ for…

Data Structures and Algorithms · Computer Science 2024-12-20 Timothy M. Chan , Ce Jin , Virginia Vassilevska Williams , Yinzhan Xu

We study the complexity of the problem of searching for a set of patterns that separate two given sets of strings. This problem has applications in a wide variety of areas, most notably in data mining, computational biology, and in…

Computational Complexity · Computer Science 2016-12-20 Giuseppe Lancia , Luke Mathieson , Pablo Moscato