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Related papers: The Dynamic k-Mismatch Problem

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We consider a class of pattern matching problems where a normalising transformation is applied at every alignment. Normalised pattern matching plays a key role in fields as diverse as image processing and musical information processing…

Data Structures and Algorithms · Computer Science 2015-03-19 Ayelet Butman , Peter Clifford , Raphael Clifford , Markus Jalsenius , Noa Lewenstein , Benny Porat , Ely Porat , Benjamin Sach

The decades-old Pattern Matching with Edits problem, given a length-$n$ string $T$ (the text), a length-$m$ string $P$ (the pattern), and a positive integer $k$ (the threshold), asks to list all fragments of $T$ that are at edit distance at…

Data Structures and Algorithms · Computer Science 2024-10-10 Tomasz Kociumaka , Jakob Nogler , Philip Wellnitz

The recently introduced longest common substring with $k$-mismatches ($k$-LCF) problem is to find, given two sequences $S_1$ and $S_2$ of length $n$ each, a longest substring $A_1$ of $S_1$ and $A_2$ of $S_2$ such that the Hamming distance…

Data Structures and Algorithms · Computer Science 2014-10-15 Szymon Grabowski

In this work, we revisit the fundamental and well-studied problem of approximate pattern matching under edit distance. Given an integer $k$, a pattern $P$ of length $m$, and a text $T$ of length $n \ge m$, the task is to find substrings of…

Data Structures and Algorithms · Computer Science 2021-06-14 Tomasz Kociumaka , Ely Porat , Tatiana Starikovskaya

We study the fundamental problem of approximating the edit distance of two strings. After an extensive line of research led to the development of a constant-factor approximation algorithm in almost-linear time, recent years have witnessed a…

Data Structures and Algorithms · Computer Science 2023-12-05 Karl Bringmann , Alejandro Cassis , Nick Fischer , Tomasz Kociumaka

The classical pattern matching asks for locating all occurrences of one string, called the pattern, in another, called the text, where a string is simply a sequence of characters. Due to the potential practical applications, it is desirable…

Data Structures and Algorithms · Computer Science 2024-10-30 Jonas Ellert , Paweł Gawrychowski , Adam Górkiewicz , Tatiana Starikovskaya

The $k$-mappability problem has two integers parameters $m$ and $k$. For every subword of size $m$ in a text $S$, we wish to report the number of indices in $S$ in which the word occurs with at most $k$ mismatches. The problem was lately…

Data Structures and Algorithms · Computer Science 2021-06-15 Amihood Amir , Itai Boneh , Eitan Kondratovsky

A central task in string processing is text indexing, where the goal is to preprocess a text (a string of length $n$) into an efficient index (a data structure) supporting queries about the text. Cole, Gottlieb, and Lewenstein (STOC 2004)…

Data Structures and Algorithms · Computer Science 2025-10-31 Tomasz Kociumaka , Jakub Radoszewski

We study the problem of estimating the edit distance between two $n$-character strings. While exact computation in the worst case is believed to require near-quadratic time, previous work showed that in certain regimes it is possible to…

Data Structures and Algorithms · Computer Science 2020-07-29 Joshua Brakensiek , Moses Charikar , Aviad Rubinstein

We show how to determine whether a given pattern p of length m occurs in a given text t of length n in ${\tilde O}(\sqrt{n}+\sqrt{m})$\footnote{${\tilde O}$ allows for logarithmic factors in m and $n/m$} time, with inverse polynomial…

Quantum Physics · Physics 2007-05-23 H. Ramesh , V. Vinay

In this paper we consider several variants of the pattern matching problem. In particular, we investigate the following problems: 1) Pattern matching with k mismatches; 2) Approximate counting of mismatches; and 3) Pattern matching with…

Data Structures and Algorithms · Computer Science 2013-07-05 Marius Nicolae , Sanguthevar Rajasekaran

The $d$-dimensional pattern matching problem is to find an occurrence of a pattern of length $m \times \dots \times m$ within a text of length $n \times \dots \times n$, with $n \ge m$. This task models various problems in text and image…

Quantum Physics · Physics 2015-08-27 Ashley Montanaro

Given an LZW/LZ78 compressed text, we want to find an approximate occurrence of a given pattern of length m. The goal is to achieve time complexity depending on the size n of the compressed representation of the text instead of its length.…

Data Structures and Algorithms · Computer Science 2013-09-23 Pawel Gawrychowski , Damian Straszak

In this work, we address the problem of approximate pattern matching with wildcards. Given a pattern $P$ of length $m$ containing $D$ wildcards, a text $T$ of length $n$, and an integer $k$, our objective is to identify all fragments of $T$…

Data Structures and Algorithms · Computer Science 2024-05-22 Gabriel Bathie , Panagiotis Charalampopoulos , Tatiana Starikovskaya

In the $(k,m)$-mappability problem, for a given sequence $T$ of length $n$, the goal is to compute a table whose $i$th entry is the number of indices $j \ne i$ such that the length-$m$ substrings of $T$ starting at positions $i$ and $j$…

Data Structures and Algorithms · Computer Science 2021-06-18 Panagiotis Charalampopoulos , Costas S. Iliopoulos , Tomasz Kociumaka , Solon P. Pissis , Jakub Radoszewski , Juliusz Straszyński

We consider a range of simply stated dynamic data structure problems on strings. An update changes one symbol in the input and a query asks us to compute some function of the pattern of length $m$ and a substring of a longer text. We give…

Data Structures and Algorithms · Computer Science 2018-02-20 Raphael Clifford , Allan Grønlund , Kasper Green Larsen , Tatiana Starikovskaya

Given strings $P$ of length $m$ and $T$ of length $n$ over an alphabet of size $\sigma$, the string matching with $k$-mismatches problem is to find the positions of all the substrings in $T$ that are at Hamming distance at most $k$ from…

Data Structures and Algorithms · Computer Science 2013-08-01 Emanuele Giaquinta , Szymon Grabowski , Kimmo Fredriksson

We revisit classic string problems considered in the area of parameterized complexity, and study them through the lens of dynamic data structures. That is, instead of asking for a static algorithm that solves the given instance efficiently,…

Data Structures and Algorithms · Computer Science 2022-05-03 Jędrzej Olkowski , Michał Pilipczuk , Mateusz Rychlicki , Karol Węgrzycki , Anna Zych-Pawlewicz

Although real-world text datasets, such as DNA sequences, are far from being uniformly random, average-case string searching algorithms perform significantly better than worst-case ones in most applications of interest. In this paper, we…

Data Structures and Algorithms · Computer Science 2018-01-16 Lorraine A. K. Ayad , Panagiotis Charalampopoulos , Costas S. Iliopoulos , Solon P. Pissis

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