English
Related papers

Related papers: Beating O(nm) in approximate LZW-compressed patter…

200 papers

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

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

Indexing highly repetitive texts --- such as genomic databases, software repositories and versioned text collections --- has become an important problem since the turn of the millennium. A relevant compressibility measure for repetitive…

Data Structures and Algorithms · Computer Science 2017-07-13 Travis Gagie , Gonzalo Navarro , Nicola Prezza

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

Dot plots are a standard method for local comparison of biological sequences. In a dot plot, a substring to substring distance is computed for all pairs of fixed-size windows in the input strings. Commonly, the Hamming distance is used…

Data Structures and Algorithms · Computer Science 2009-09-11 Peter Krusche , Alexander Tiskin

We consider the problem of computing distance between a pattern of length $n$ and all $n$-length subwords of a text in the streaming model. In the streaming setting, only the Hamming distance ($L_0$) has been studied. It is known that…

Data Structures and Algorithms · Computer Science 2020-11-10 Tatiana Starikovskaya , Michal Svagerka , Przemysław Uznański

We study the approximate string matching and regular expression matching problem for the case when the text to be searched is compressed with the Ziv-Lempel adaptive dictionary compression schemes. We present a time-space trade-off that…

Data Structures and Algorithms · Computer Science 2007-05-23 Philip Bille , Rolf Fagerberg , Inge Li Goertz

The Lempel-Ziv parsing of a string (LZ77 for short) is one of the most important and widely-used algorithmic tools in data compression and string processing. We show that the Lempel-Ziv parsing of a string of length $n$ on an alphabet of…

Data Structures and Algorithms · Computer Science 2015-07-28 Djamal Belazzougui , Simon J. Puglisi

The Cartesian tree of a sequence captures the relative order of the sequence's elements. In recent years, Cartesian tree matching has attracted considerable attention, particularly due to its applications in time series analysis. Consider a…

Data Structures and Algorithms · Computer Science 2026-02-10 Panagiotis Charalampopoulos , Jonas Ellert , Manal Mohamed

Countless variants of the Lempel-Ziv compression are widely used in many real-life applications. This paper is concerned with a natural modification of the classical pattern matching problem inspired by the popularity of such compression…

Data Structures and Algorithms · Computer Science 2011-04-22 Pawel Gawrychowski

Various grammar compression algorithms have been proposed in the last decade. A grammar compression is a restricted CFG deriving the string deterministically. An efficient grammar compression develops a smaller CFG by finding duplicated…

Data Structures and Algorithms · Computer Science 2016-09-01 Shouhei Fukunaga , Yoshimasa Takabatake , I Tomohiro , Hiroshi Sakamoto

We study the problem of estimating the size of a maximum matching in sublinear time. The problem has been studied extensively in the literature and various algorithms and lower bounds are known for it. Our result is a $0.5109$-approximation…

Data Structures and Algorithms · Computer Science 2025-06-03 Sepideh Mahabadi , Mohammad Roghani , Jakub Tarnawski

We describe the first self-indexes able to count and locate pattern occurrences in optimal time within a space bounded by the size of the most popular dictionary compressors. To achieve this result we combine several recent findings,…

Data Structures and Algorithms · Computer Science 2019-09-06 Anders Roy Christiansen , Mikko Berggren Ettienne , Tomasz Kociumaka , Gonzalo Navarro , Nicola Prezza

In this paper, we propose a new \emph{dynamic compressed index} of $O(w)$ space for a dynamic text $T$, where $w = O(\min(z \log N \log^*M, N))$ is the size of the signature encoding of $T$, $z$ is the size of the Lempel-Ziv77 (LZ77)…

Data Structures and Algorithms · Computer Science 2016-07-20 Takaaki Nishimoto , Tomohiro I , Shunsuke Inenaga , Hideo Bannai , Masayuki Takeda

We raise the question of approximating the compressibility of a string with respect to a fixed compression scheme, in sublinear time. We study this question in detail for two popular lossless compression schemes: run-length encoding (RLE)…

Data Structures and Algorithms · Computer Science 2007-06-11 Sofya Raskhodnikova , Dana Ron , Ronitt Rubinfeld , Adam Smith

In many applications, it is necessary to determine the string similarity. Edit distance[WF74] approach is a classic method to determine Field Similarity. A well known dynamic programming algorithm [GUS97] is used to calculate edit distance…

Data Structures and Algorithms · Computer Science 2007-05-23 Qi Xiao Yang , Sung Sam Yuan , Lu Chun , Li Zhao , Sun Peng

The classic exact pattern matching problem, given two strings -- a pattern $P$ of length $m$ and a text $T$ of length $n$ -- asks whether $P$ occurs as a substring of $T$. A property tester for the problem needs to distinguish (with high…

Data Structures and Algorithms · Computer Science 2025-10-21 Ce Jin , Tomasz Kociumaka

Given a string $S$, the \emph{compressed indexing problem} is to preprocess $S$ into a compressed representation that supports fast \emph{substring queries}. The goal is to use little space relative to the compressed size of $S$ while…

Data Structures and Algorithms · Computer Science 2018-01-10 Philip Bille , Mikko Berggren Ettienne , Inge Li Gørtz , Hjalte Wedel Vildhøj

Dynamic Time Warping (DTW) is a widely used similarity measure for comparing strings that encode time series data, with applications to areas including bioinformatics, signature verification, and speech recognition. The standard…

Data Structures and Algorithms · Computer Science 2022-07-05 Zoe Xi , William Kuszmaul

Given a string $T$ of length $N$, the goal of grammar compression is to construct a small context-free grammar generating only $T$. Among existing grammar compression methods, RePair (recursive paring) [Larsson and Moffat, 1999] is notable…

Data Structures and Algorithms · Computer Science 2018-11-06 Kensuke Sakai , Tatsuya Ohno , Keisuke Goto , Yoshimasa Takabatake , Tomohiro I , Hiroshi Sakamoto