Journal of Computer and System Sciences最新文献_第4页

A linear algorithm for radio k-coloring of powers of paths having small diameters 小直径路径幂的无线电 k 着色线性算法

IF 1.1 3区计算机科学

Journal of Computer and System Sciences Pub Date : 2024-08-26 DOI: 10.1016/j.jcss.2024.103577

Dipayan Chakraborty , Soumen Nandi , Sagnik Sen , D.K. Supraja

{"title":"A linear algorithm for radio k-coloring of powers of paths having small diameters","authors":"Dipayan Chakraborty , Soumen Nandi , Sagnik Sen , D.K. Supraja","doi":"10.1016/j.jcss.2024.103577","DOIUrl":"10.1016/j.jcss.2024.103577","url":null,"abstract":"<div>The radio k-chromatic number <math><mi>r</mi><msub><mrow><mi>c</mi></mrow><mrow><mi>k</mi></mrow></msub><mo>(</mo><mi>G</mi><mo>)</mo></math> of a graph G is the minimum integer λ such that there exists a function <math><mi>ϕ</mi><mo>:</mo><mi>V</mi><mo>(</mo><mi>G</mi><mo>)</mo><mo>→</mo><mo>{</mo><mn>0</mn><mo>,</mo><mn>1</mn><mo>,</mo><mo>⋯</mo><mo>,</mo><mi>λ</mi><mo>}</mo></math> satisfying <math><mo>|</mo><mi>ϕ</mi><mo>(</mo><mi>u</mi><mo>)</mo><mo>−</mo><mi>ϕ</mi><mo>(</mo><mi>v</mi><mo>)</mo><mo>|</mo><mo>≥</mo><mi>k</mi><mo>+</mo><mn>1</mn><mo>−</mo><mi>d</mi><mo>(</mo><mi>u</mi><mo>,</mo><mi>v</mi><mo>)</mo></math>, where <math><mi>d</mi><mo>(</mo><mi>u</mi><mo>,</mo><mi>v</mi><mo>)</mo></math> denotes the distance between u and v. A considerable amount of attention has been given to find the exact values or providing polynomial time algorithms to determine <math><mi>r</mi><msub><mrow><mi>c</mi></mrow><mrow><mi>k</mi></mrow></msub><mo>(</mo><mi>G</mi><mo>)</mo></math> for several basic graph families such as paths, cycles, trees, and powers of paths, usually for some specific values of k. In this article, we find the exact values of <math><mi>r</mi><msub><mrow><mi>c</mi></mrow><mrow><mi>k</mi></mrow></msub><mo>(</mo><mi>G</mi><mo>)</mo></math> where G is a power of a path with diameter strictly less than k. Our proof readily provides a linear time algorithm for assigning a radio k-coloring of G. Furthermore, our proof technique is a potential tool for solving the same problem for other classes of graphs having “small” diameters.</div>","PeriodicalId":50224,"journal":{"name":"Journal of Computer and System Sciences","volume":"147 ","pages":"Article 103577"},"PeriodicalIF":1.1,"publicationDate":"2024-08-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142136727","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

On finding short reconfiguration sequences between independent sets 关于在独立集合之间寻找短重组序列

IF 1.1 3区计算机科学

Journal of Computer and System Sciences Pub Date : 2024-08-23 DOI: 10.1016/j.jcss.2024.103578

Akanksha Agrawal , Soumita Hait , Amer E. Mouawad

{"title":"On finding short reconfiguration sequences between independent sets","authors":"Akanksha Agrawal , Soumita Hait , Amer E. Mouawad","doi":"10.1016/j.jcss.2024.103578","DOIUrl":"10.1016/j.jcss.2024.103578","url":null,"abstract":"<div>Token Sliding Optimization asks whether there exists a sequence of at most ℓ steps that transforms independent set S into T, where at each step a token slides to an unoccupied neighboring vertex (while maintaining independence). In Token Jumping Optimization, we are instead allowed to jump from a vertex to any unoccupied vertex. Both problems are known to be FPT when parameterized by ℓ on nowhere dense graphs. In this work, we show that both problems are FPT for parameter <math><mi>k</mi><mo>+</mo><mi>ℓ</mi><mo>+</mo><mi>d</mi></math> on d-degenerate graphs as well as for parameter <math><mo>|</mo><mi>M</mi><mo>|</mo><mo>+</mo><mi>ℓ</mi><mo>+</mo><mi>Δ</mi></math> on graphs having a modulator M to maximum degree Δ. We complement these results by showing that for parameter ℓ both problems become hard already on 2-degenerate graphs. Finally, we show that using such families one can obtain a unified algorithm for the standard Token Jumping problem parameterized by k on degenerate and nowhere dense graphs.</div>","PeriodicalId":50224,"journal":{"name":"Journal of Computer and System Sciences","volume":"147 ","pages":"Article 103578"},"PeriodicalIF":1.1,"publicationDate":"2024-08-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142084354","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Minimum separator reconfiguration 最小分离器重新配置

IF 1.1 3区计算机科学

Journal of Computer and System Sciences Pub Date : 2024-07-29 DOI: 10.1016/j.jcss.2024.103574

Guilherme C.M. Gomes , Clément Legrand-Duchesne , Reem Mahmoud , Amer E. Mouawad , Yoshio Okamoto , Vinicius F. dos Santos , Tom C. van der Zanden

{"title":"Minimum separator reconfiguration","authors":"Guilherme C.M. Gomes , Clément Legrand-Duchesne , Reem Mahmoud , Amer E. Mouawad , Yoshio Okamoto , Vinicius F. dos Santos , Tom C. van der Zanden","doi":"10.1016/j.jcss.2024.103574","DOIUrl":"10.1016/j.jcss.2024.103574","url":null,"abstract":"<div>We study the problem of reconfiguring s-t-separators on finite simple graphs. We consider several variants of the problem, focusing on the token sliding and jumping models. We begin with a polynomial-time algorithm that computes (if one exists) a shortest sequence of slides and another that decides if a sequence of jumps exists and outputs a witnessing sequence. We also show that deciding if a reconfiguration sequence of at most ℓ jumps exists is an <math><mtext>NP</mtext></math>-complete problem. To complement this result, we investigate the parameterized complexity of the natural parameterizations of the problem: by the size k of the minimum s-t-separators and by the number of jumps ℓ. We show that the problem is in FPT parameterized by k, but that it does not admit a polynomial kernel unless <math><mtext>NP</mtext><mo>⊆</mo><mtext>coNP/poly</mtext></math>. Our final result is a kernel with <math><mi>O</mi><mo>(</mo><msup><mrow><mi>ℓ</mi></mrow><mrow><mn>2</mn></mrow></msup><mo>)</mo></math> vertices and edges.</div>","PeriodicalId":50224,"journal":{"name":"Journal of Computer and System Sciences","volume":"146 ","pages":"Article 103574"},"PeriodicalIF":1.1,"publicationDate":"2024-07-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141936525","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Towards declarative comparabilities: Application to functional dependencies 实现声明式比较：应用于功能依赖性

IF 1.1 3区计算机科学

Journal of Computer and System Sciences Pub Date : 2024-07-29 DOI: 10.1016/j.jcss.2024.103576

Lhouari Nourine , Jean-Marc Petit , Simon Vilmin

引用次数: 0

Modular SAT-based techniques for reasoning tasks in team semantics 基于模块化 SAT 的团队语义推理任务技术

IF 1.1 3区计算机科学

Journal of Computer and System Sciences Pub Date : 2024-07-25 DOI: 10.1016/j.jcss.2024.103575

Arnaud Durand , Juha Kontinen , Jouko Väänänen

引用次数: 0

The complexity of computing optimum labelings for temporal connectivity 计算时空连通性最佳标签的复杂性

IF 1.1 3区计算机科学

Journal of Computer and System Sciences Pub Date : 2024-07-09 DOI: 10.1016/j.jcss.2024.103564

Nina Klobas , George B. Mertzios , Hendrik Molter , Paul G. Spirakis

{"title":"The complexity of computing optimum labelings for temporal connectivity","authors":"Nina Klobas , George B. Mertzios , Hendrik Molter , Paul G. Spirakis","doi":"10.1016/j.jcss.2024.103564","DOIUrl":"10.1016/j.jcss.2024.103564","url":null,"abstract":"<div>A graph is temporally connected if a strict temporal path exists from every vertex u to every other vertex v. This paper studies temporal design problems for undirected temporally connected graphs. Given a connected undirected graph G, the goal is to determine the smallest total number of time-labels <math><mo>|</mo><mi>λ</mi><mo>|</mo></math> needed to ensure temporal connectivity, where <math><mo>|</mo><mi>λ</mi><mo>|</mo></math> denotes the sum, over all edges, of the size of the set of labels associated to an edge. The basic problem, called Minimum Labeling (ML) can be solved optimally in polynomial time. We introduce the Min. Aged Labeling (MAL) problem, which involves connecting the graph with an upper-bound on the maximum label, the Min. Steiner Labeling (MSL) problem, focusing on connecting specific important vertices, and the age-restricted version of MSL, Min. Aged Steiner Labeling (MASL). We show that MAL is NP-complete, MASL is W[1]-hard, and while MSL remains NP-hard, it is FPT with respect to the number of terminals.</div>","PeriodicalId":50224,"journal":{"name":"Journal of Computer and System Sciences","volume":"146 ","pages":"Article 103564"},"PeriodicalIF":1.1,"publicationDate":"2024-07-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S002200002400059X/pdfft?md5=47d92c214e02fc0c658d2c49a1fdf6d8&pid=1-s2.0-S002200002400059X-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141719050","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

The impact of state merging on predictive accuracy in probabilistic tree automata: Dietze's conjecture revisited 状态合并对概率树自动机预测准确性的影响：迪茨猜想再探讨

IF 1.1 3区计算机科学

Journal of Computer and System Sciences Pub Date : 2024-06-27 DOI: 10.1016/j.jcss.2024.103563

{"title":"The impact of state merging on predictive accuracy in probabilistic tree automata: Dietze's conjecture revisited","authors":"","doi":"10.1016/j.jcss.2024.103563","DOIUrl":"10.1016/j.jcss.2024.103563","url":null,"abstract":"<div>Dietze's conjecture concerns the problem of equipping a tree automaton M with weights to make it probabilistic, in such a way that the resulting automaton N predicts a given corpus <math><mi>C</mi></math> as accurately as possible. The conjecture states that the accuracy cannot increase if the states in M are merged with respect to an equivalence relation ∼ so that the result is a smaller automaton <math><msup><mrow><mi>M</mi></mrow><mrow><mo>∼</mo></mrow></msup></math>. Put differently, merging states can never improve predictions. This is under the assumption that both M and <math><msup><mrow><mi>M</mi></mrow><mrow><mo>∼</mo></mrow></msup></math> are bottom-up deterministic and accept every tree in <math><mi>C</mi></math>. We prove that the conjecture holds, using a construction that turns any probabilistic version <math><msup><mrow><mi>N</mi></mrow><mrow><mo>∼</mo></mrow></msup></math> of <math><msup><mrow><mi>M</mi></mrow><mrow><mo>∼</mo></mrow></msup></math> into a probabilistic version N of M, such that N assigns at least as great a weight to each tree in <math><mi>C</mi></math> as <math><msup><mrow><mi>N</mi></mrow><mrow><mo>∼</mo></mrow></msup></math> does.</div>","PeriodicalId":50224,"journal":{"name":"Journal of Computer and System Sciences","volume":"146 ","pages":"Article 103563"},"PeriodicalIF":1.1,"publicationDate":"2024-06-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S0022000024000588/pdfft?md5=9e1c1d599bbcfc040fd29b857c6c21e8&pid=1-s2.0-S0022000024000588-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141571800","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Corrigendum to “Homomorphism preservation on quasi-wide classes” [J. Comput. Syst. Sci. 76 (5) (2010) 324–332] 准广类上的同态保存》更正 [J. Comput. Syst.

IF 1.1 3区计算机科学

Journal of Computer and System Sciences Pub Date : 2024-06-10 DOI: 10.1016/j.jcss.2024.103553

Anuj Dawar

引用次数: 0

The g-extra connectivity of graph products 图积的 g 外连接性

IF 1.1 3区计算机科学

Journal of Computer and System Sciences Pub Date : 2024-05-29 DOI: 10.1016/j.jcss.2024.103552

Zhao Wang , Yaping Mao , Sun-Yuan Hsieh , Ralf Klasing , Yuzhi Xiao

{"title":"The g-extra connectivity of graph products","authors":"Zhao Wang , Yaping Mao , Sun-Yuan Hsieh , Ralf Klasing , Yuzhi Xiao","doi":"10.1016/j.jcss.2024.103552","DOIUrl":"10.1016/j.jcss.2024.103552","url":null,"abstract":"<div>Connectivity is one of important parameters for the fault tolerant of an interconnection network. In 1996, Fàbrega and Fiol proposed the concept of g-extra connectivity. A subset of vertices S is said to be a cutset if <math><mi>G</mi><mo>−</mo><mi>S</mi></math> is not connected. A cutset S is called an <math><msub><mrow><mi>R</mi></mrow><mrow><mi>g</mi></mrow></msub></math>-cutset, where g is a non-negative integer, if every component of <math><mi>G</mi><mo>−</mo><mi>S</mi></math> has at least <math><mi>g</mi><mo>+</mo><mn>1</mn></math> vertices. If G has at least one <math><msub><mrow><mi>R</mi></mrow><mrow><mi>g</mi></mrow></msub></math>-cutset, the g-extra connectivity of G, denoted by <math><msub><mrow><mi>κ</mi></mrow><mrow><mi>g</mi></mrow></msub><mo>(</mo><mi>G</mi><mo>)</mo></math>, is then defined as the minimum cardinality over all <math><msub><mrow><mi>R</mi></mrow><mrow><mi>g</mi></mrow></msub></math>-cutsets of G. In this paper, we first obtain the exact value of g-extra connectivity for the lexicographic product of two general graphs. Next, the upper and lower sharp bounds of g-extra connectivity for the Cartesian product of two general graphs are given. In the end, we apply our results on grid graphs and 2-dimensional generalized hypercubes.</div>","PeriodicalId":50224,"journal":{"name":"Journal of Computer and System Sciences","volume":"145 ","pages":"Article 103552"},"PeriodicalIF":1.1,"publicationDate":"2024-05-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141195346","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

On computing large temporal (unilateral) connected components 关于计算大时间（单边）连接成分

IF 1.1 3区计算机科学

Journal of Computer and System Sciences Pub Date : 2024-05-22 DOI: 10.1016/j.jcss.2024.103548

Isnard Lopes Costa , Raul Lopes , Andrea Marino , Ana Silva

引用次数: 0