English
Related papers

Related papers: On improving the approximation ratio of the r-shor…

200 papers

In this paper, we define the reoptimization variant of the closest substring problem (CSP) under sequence addition. We show that, even with the additional information we have about the problem instance, the problem of finding a closest…

Data Structures and Algorithms · Computer Science 2016-03-09 Jeffrey Aborot , Henry Adorna , Jhoirene Clemente

We present novel randomized approximation schemes for the Edit Distance (ED) problem and the Longest Common Subsequence (LCS) problem that, for any constant $\epsilon>0$, compute a $(1+\epsilon)$-approximation for ED and a…

Data Structures and Algorithms · Computer Science 2026-04-01 Xiao Mao , Aviad Rubinstein

Let $\Sigma$ be an alphabet. For two strings $X$, $Y$, and a constrained string $P$ over the alphabet $\Sigma$, the constrained longest common subsequence and substring problem for two strings $X$ and $Y$ with respect to $P$ is to find a…

Data Structures and Algorithms · Computer Science 2023-08-04 R. Li , J. Deka , K. Deka , D. Li

In this paper we define a new problem, motivated by computational biology, $LCSk$ aiming at finding the maximal number of $k$ length $substrings$, matching in both input strings while preserving their order of appearance. The traditional…

Data Structures and Algorithms · Computer Science 2014-02-11 Gary Benson , Avivit Levy , Riva Shalom

In this note, we first introduce a new problem called the longest common subsequence and substring problem. Let $X$ and $Y$ be two strings over an alphabet $\Sigma$. The longest common subsequence and substring problem for $X$ and $Y$ is to…

Data Structures and Algorithms · Computer Science 2023-08-03 R. Li , J. Deka , K. Deka

A technique using a systolic array structure is proposed for solving the common approximate substring (CAS) problem. This approach extends the technique introduced in earlier work from the computation of the edit-distance between two…

Data Structures and Algorithms · Computer Science 2010-06-08 Jacqueline E. Rice , Kenneth B. Kent

We revisit the classic combinatorial pattern matching problem of finding a longest common subsequence (LCS). For strings $x$ and $y$ of length $n$, a textbook algorithm solves LCS in time $O(n^2)$, but although much effort has been spent,…

Computational Complexity · Computer Science 2018-03-05 Karl Bringmann , Marvin Künnemann

We revisit the problem of finding shortest unique substring (SUS) proposed recently by [6]. We propose an optimal $O(n)$ time and space algorithm that can find an SUS for every location of a string of size $n$. Our algorithm significantly…

Data Structures and Algorithms · Computer Science 2014-01-14 Atalay Mert İleri , M. Oğuzhan Külekci , Bojian Xu

We study the fundamental problem of finding the best string to represent a given set, in the form of the Closest String problem: Given a set $X \subseteq \Sigma^d$ of $n$ strings, find the string $x^*$ minimizing the radius of the smallest…

Computational Complexity · Computer Science 2023-05-30 Amir Abboud , Nick Fischer , Elazar Goldenberg , Karthik C. S. , Ron Safier

At CPM 2017, Castelli et al. define and study a new variant of the Longest Common Subsequence Problem, termed the Longest Filled Common Subsequence Problem (LFCS). For the LFCS problem, the input consists of two strings $A$ and $B$ and a…

Data Structures and Algorithms · Computer Science 2019-08-06 Radu Stefan Mincu , Alexandru Popa

The longest common substring problem consists in finding a longest string that appears as a (contiguous) substring of two input strings. We consider the dynamic variant of this problem, in which we are to maintain two dynamic strings $S$…

Data Structures and Algorithms · Computer Science 2026-04-09 Panagiotis Charalampopoulos , Paweł Gawrychowski , Karol Pokorski

In this paper, we consider a generalized longest common subsequence problem with multiple substring inclusive constraints. For the two input sequences $X$ and $Y$ of lengths $n$ and $m$, and a set of $d$ constraints $P=\{P_1,\cdots,P_d\}$…

Data Structures and Algorithms · Computer Science 2015-05-26 Daxin Zhu , Lei Wang , Yingjie Wu , Xiaodong Wang

We revisit two well-known algorithmic problems on strings: computing a shortest unique substring (SUS) and a shortest absent substring (SAS) of a string $S$ of length $n$. Both problems admit folklore $\mathcal{O}(n)$-time solutions using…

Data Structures and Algorithms · Computer Science 2026-05-07 Panagiotis Charalampopoulos , Manal Mohamed , Solon P. Pissis , Hilde Verbeek , Wiktor Zuba

We revisit the Stochastic Score Classification (SSC) problem introduced by Gkenosis et al. (ESA 2018): We are given $n$ tests. Each test $j$ can be conducted at cost $c_j$, and it succeeds independently with probability $p_j$. Further, a…

Data Structures and Algorithms · Computer Science 2024-01-23 Benedikt M. Plank , Kevin Schewior

Approximate string matching is the problem of finding all factors of a text t of length n that are at a distance at most k from a pattern x of length m. Approximate circular string matching is the problem of finding all factors of t that…

Data Structures and Algorithms · Computer Science 2016-04-26 Carl Barton , Costas S. Iliopoulos , Solon P. Pissis

In the usual trace reconstruction problem, the goal is to exactly reconstruct an unknown string of length $n$ after it passes through a deletion channel many times independently, producing a set of traces (i.e., random subsequences of the…

Data Structures and Algorithms · Computer Science 2020-12-17 Sami Davies , Miklos Z. Racz , Cyrus Rashtchian , Benjamin G. Schiffer

The {\em longest common subsequence (LCS)} problem is a classic and well-studied problem in computer science. LCS is a central problem in stringology and finds broad applications in text compression, error-detecting codes and biological…

Data Structures and Algorithms · Computer Science 2010-04-20 Shihabur Rahman Chowdhury , Masud Hasan , Sumaiya Iqbal , M. Sohel Rahman

The Average Common Substring (ACS) is a popular alignment-free distance measure for phylogeny reconstruction. The ACS can be computed in O(n) space and time, where n=x+y is the input size. The compressed string matching is the study of…

Data Structures and Algorithms · Computer Science 2018-05-17 Sahar Hooshmand , Neda Tavakoli , Paniz Abedin , Sharma V. Thankachan

Covers are a kind of quasiperiodicity in strings. A string $C$ is a cover of another string $T$ if any position of $T$ is inside some occurrence of $C$ in $T$. The shortest and longest cover arrays of $T$ have the lengths of the shortest…

Data Structures and Algorithms · Computer Science 2020-07-31 Natsumi Kikuchi , Diptarama Hendrian , Ryo Yoshinaka , Ayumi Shinohara

We consider the problem of finding, given two documents of total length $n$, a longest string occurring as a substring of both documents. This problem, known as the Longest Common Substring (LCS) problem, has a classic $O(n)$-time solution…

Data Structures and Algorithms · Computer Science 2020-04-29 Stav Ben-Nun , Shay Golan , Tomasz Kociumaka , Matan Kraus