D. Karthika , R. Muthucumaraswamy , Sriram Bhyravarapu , Pritesh Kumar
{"title":"完美图子类上的跳支配","authors":"D. Karthika , R. Muthucumaraswamy , Sriram Bhyravarapu , Pritesh Kumar","doi":"10.1016/j.tcs.2025.115547","DOIUrl":null,"url":null,"abstract":"<div><div>A set <span><math><mrow><mi>S</mi><mo>⊆</mo><mi>V</mi><mo>(</mo><mi>G</mi><mo>)</mo></mrow></math></span> is said to be a <em>hop dominating set</em> if every vertex <span><math><mrow><mi>u</mi><mo>∈</mo><mi>V</mi><mo>(</mo><mi>G</mi><mo>)</mo><mo>∖</mo><mi>S</mi></mrow></math></span>, there exists a vertex <span><math><mrow><mi>v</mi><mo>∈</mo><mi>S</mi></mrow></math></span> such that <span><math><mrow><mi>d</mi><mo>(</mo><mi>u</mi><mo>,</mo><mi>v</mi><mo>)</mo><mo>=</mo><mn>2</mn></mrow></math></span> where <span><math><mrow><mi>d</mi><mo>(</mo><mi>u</mi><mo>,</mo><mi>v</mi><mo>)</mo></mrow></math></span> represents the distance between <span><math><mi>u</mi></math></span> and <span><math><mi>v</mi></math></span> in <span><math><mi>G</mi></math></span>. Given a graph <span><math><mi>G</mi></math></span>, <span>Hop Domination</span> asks to find the minimum size of a hop dominating set of <span><math><mi>G</mi></math></span>, also called the <em>hop domination number</em>. Henning et al. (Graphs Combin. 2017) showed that <span>Hop Domination</span> is <span>NP</span>-hard for bipartite graphs and chordal graphs. Since the class of chordal graphs is contained in the class of perfect graphs, the problem is <span>NP</span>-hard on perfect graphs. We would like to study the complexity of the problem on subclasses of perfect graphs and understand where the complexity of the problem shifts from tractable to intractable.</div><div>The following are the results of this paper. We present polynomial algorithms for <span>Hop Domination</span> on permutation graphs, interval graphs and biconvex bipartite graphs. This generalizes the polynomial time algorithm for <span>Hop Domination</span> on bipartite permutation graphs. We also initiate a study on this problem from the parameterized complexity perspective. We show that the decision version of <span>Hop Domination</span> is <span><math><mrow><mi>W</mi><mo>[</mo><mn>2</mn><mo>]</mo></mrow></math></span>-hard when parameterized by solution size.</div></div>","PeriodicalId":49438,"journal":{"name":"Theoretical Computer Science","volume":"1057 ","pages":"Article 115547"},"PeriodicalIF":1.0000,"publicationDate":"2025-09-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"Hop domination on subclasses of perfect graphs\",\"authors\":\"D. Karthika , R. Muthucumaraswamy , Sriram Bhyravarapu , Pritesh Kumar\",\"doi\":\"10.1016/j.tcs.2025.115547\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<div><div>A set <span><math><mrow><mi>S</mi><mo>⊆</mo><mi>V</mi><mo>(</mo><mi>G</mi><mo>)</mo></mrow></math></span> is said to be a <em>hop dominating set</em> if every vertex <span><math><mrow><mi>u</mi><mo>∈</mo><mi>V</mi><mo>(</mo><mi>G</mi><mo>)</mo><mo>∖</mo><mi>S</mi></mrow></math></span>, there exists a vertex <span><math><mrow><mi>v</mi><mo>∈</mo><mi>S</mi></mrow></math></span> such that <span><math><mrow><mi>d</mi><mo>(</mo><mi>u</mi><mo>,</mo><mi>v</mi><mo>)</mo><mo>=</mo><mn>2</mn></mrow></math></span> where <span><math><mrow><mi>d</mi><mo>(</mo><mi>u</mi><mo>,</mo><mi>v</mi><mo>)</mo></mrow></math></span> represents the distance between <span><math><mi>u</mi></math></span> and <span><math><mi>v</mi></math></span> in <span><math><mi>G</mi></math></span>. Given a graph <span><math><mi>G</mi></math></span>, <span>Hop Domination</span> asks to find the minimum size of a hop dominating set of <span><math><mi>G</mi></math></span>, also called the <em>hop domination number</em>. Henning et al. (Graphs Combin. 2017) showed that <span>Hop Domination</span> is <span>NP</span>-hard for bipartite graphs and chordal graphs. Since the class of chordal graphs is contained in the class of perfect graphs, the problem is <span>NP</span>-hard on perfect graphs. We would like to study the complexity of the problem on subclasses of perfect graphs and understand where the complexity of the problem shifts from tractable to intractable.</div><div>The following are the results of this paper. We present polynomial algorithms for <span>Hop Domination</span> on permutation graphs, interval graphs and biconvex bipartite graphs. This generalizes the polynomial time algorithm for <span>Hop Domination</span> on bipartite permutation graphs. We also initiate a study on this problem from the parameterized complexity perspective. We show that the decision version of <span>Hop Domination</span> is <span><math><mrow><mi>W</mi><mo>[</mo><mn>2</mn><mo>]</mo></mrow></math></span>-hard when parameterized by solution size.</div></div>\",\"PeriodicalId\":49438,\"journal\":{\"name\":\"Theoretical Computer Science\",\"volume\":\"1057 \",\"pages\":\"Article 115547\"},\"PeriodicalIF\":1.0000,\"publicationDate\":\"2025-09-14\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Theoretical Computer Science\",\"FirstCategoryId\":\"94\",\"ListUrlMain\":\"https://www.sciencedirect.com/science/article/pii/S0304397525004852\",\"RegionNum\":4,\"RegionCategory\":\"计算机科学\",\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q3\",\"JCRName\":\"COMPUTER SCIENCE, THEORY & METHODS\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Theoretical Computer Science","FirstCategoryId":"94","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S0304397525004852","RegionNum":4,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q3","JCRName":"COMPUTER SCIENCE, THEORY & METHODS","Score":null,"Total":0}
A set is said to be a hop dominating set if every vertex , there exists a vertex such that where represents the distance between and in . Given a graph , Hop Domination asks to find the minimum size of a hop dominating set of , also called the hop domination number. Henning et al. (Graphs Combin. 2017) showed that Hop Domination is NP-hard for bipartite graphs and chordal graphs. Since the class of chordal graphs is contained in the class of perfect graphs, the problem is NP-hard on perfect graphs. We would like to study the complexity of the problem on subclasses of perfect graphs and understand where the complexity of the problem shifts from tractable to intractable.
The following are the results of this paper. We present polynomial algorithms for Hop Domination on permutation graphs, interval graphs and biconvex bipartite graphs. This generalizes the polynomial time algorithm for Hop Domination on bipartite permutation graphs. We also initiate a study on this problem from the parameterized complexity perspective. We show that the decision version of Hop Domination is -hard when parameterized by solution size.
期刊介绍:
Theoretical Computer Science is mathematical and abstract in spirit, but it derives its motivation from practical and everyday computation. Its aim is to understand the nature of computation and, as a consequence of this understanding, provide more efficient methodologies. All papers introducing or studying mathematical, logic and formal concepts and methods are welcome, provided that their motivation is clearly drawn from the field of computing.