{"title":"非循环匹配的参数化结果及其对相关问题的影响","authors":"Juhi Chaudhary , Meirav Zehavi","doi":"10.1016/j.jcss.2024.103599","DOIUrl":null,"url":null,"abstract":"<div><div>A matching <em>M</em> in a graph <em>G</em> is an <em>acyclic matching</em> if the subgraph of <em>G</em> induced by the endpoints of the edges of <em>M</em> is a forest. Given a graph <em>G</em> and <span><math><mi>ℓ</mi><mo>∈</mo><mi>N</mi></math></span>, <span>Acyclic Matching</span> asks whether <em>G</em> has an acyclic matching of <em>size</em> at least <em>ℓ</em>. In this paper, we prove that assuming <span><math><mi>W</mi><mo>[</mo><mn>1</mn><mo>]</mo><mo>⊈</mo><mi>FPT</mi></math></span>, there does not exist any <span><math><mi>FPT</mi></math></span>-approximation algorithm for <span>Acyclic Matching</span> that approximates it within a constant factor when parameterized by <em>ℓ</em>. Our reduction also asserts <span><math><mi>FPT</mi></math></span>-inapproximability for <span>Induced Matching</span> and <span>Uniquely Restricted Matching</span>. We also consider three below-guarantee parameters for <span>Acyclic Matching</span>, viz. <span><math><mfrac><mrow><mi>n</mi></mrow><mrow><mn>2</mn></mrow></mfrac><mo>−</mo><mi>ℓ</mi></math></span>, <span><math><mrow><mi>MM</mi><mo>(</mo><mi>G</mi><mo>)</mo></mrow><mo>−</mo><mi>ℓ</mi></math></span>, and <span><math><mrow><mi>IS</mi><mo>(</mo><mi>G</mi><mo>)</mo></mrow><mo>−</mo><mi>ℓ</mi></math></span>, where <span><math><mi>n</mi><mo>=</mo><mi>V</mi><mo>(</mo><mi>G</mi><mo>)</mo></math></span>, <span><math><mi>MM</mi><mo>(</mo><mi>G</mi><mo>)</mo></math></span> is the <em>matching number</em>, and <span><math><mi>IS</mi><mo>(</mo><mi>G</mi><mo>)</mo></math></span> is the <em>independence number</em> of <em>G</em>. Also, we show that <span>Acyclic Matching</span> does not exhibit a polynomial kernel with respect to vertex cover number (or vertex deletion distance to clique) plus the size of the matching unless <span><math><mrow><mi>NP</mi></mrow><mo>⊆</mo><mrow><mi>coNP</mi></mrow><mo>/</mo><mrow><mi>poly</mi></mrow></math></span>.</div></div>","PeriodicalId":50224,"journal":{"name":"Journal of Computer and System Sciences","volume":"148 ","pages":"Article 103599"},"PeriodicalIF":1.1000,"publicationDate":"2024-10-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"Parameterized results on acyclic matchings with implications for related problems\",\"authors\":\"Juhi Chaudhary , Meirav Zehavi\",\"doi\":\"10.1016/j.jcss.2024.103599\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<div><div>A matching <em>M</em> in a graph <em>G</em> is an <em>acyclic matching</em> if the subgraph of <em>G</em> induced by the endpoints of the edges of <em>M</em> is a forest. Given a graph <em>G</em> and <span><math><mi>ℓ</mi><mo>∈</mo><mi>N</mi></math></span>, <span>Acyclic Matching</span> asks whether <em>G</em> has an acyclic matching of <em>size</em> at least <em>ℓ</em>. In this paper, we prove that assuming <span><math><mi>W</mi><mo>[</mo><mn>1</mn><mo>]</mo><mo>⊈</mo><mi>FPT</mi></math></span>, there does not exist any <span><math><mi>FPT</mi></math></span>-approximation algorithm for <span>Acyclic Matching</span> that approximates it within a constant factor when parameterized by <em>ℓ</em>. Our reduction also asserts <span><math><mi>FPT</mi></math></span>-inapproximability for <span>Induced Matching</span> and <span>Uniquely Restricted Matching</span>. We also consider three below-guarantee parameters for <span>Acyclic Matching</span>, viz. <span><math><mfrac><mrow><mi>n</mi></mrow><mrow><mn>2</mn></mrow></mfrac><mo>−</mo><mi>ℓ</mi></math></span>, <span><math><mrow><mi>MM</mi><mo>(</mo><mi>G</mi><mo>)</mo></mrow><mo>−</mo><mi>ℓ</mi></math></span>, and <span><math><mrow><mi>IS</mi><mo>(</mo><mi>G</mi><mo>)</mo></mrow><mo>−</mo><mi>ℓ</mi></math></span>, where <span><math><mi>n</mi><mo>=</mo><mi>V</mi><mo>(</mo><mi>G</mi><mo>)</mo></math></span>, <span><math><mi>MM</mi><mo>(</mo><mi>G</mi><mo>)</mo></math></span> is the <em>matching number</em>, and <span><math><mi>IS</mi><mo>(</mo><mi>G</mi><mo>)</mo></math></span> is the <em>independence number</em> of <em>G</em>. Also, we show that <span>Acyclic Matching</span> does not exhibit a polynomial kernel with respect to vertex cover number (or vertex deletion distance to clique) plus the size of the matching unless <span><math><mrow><mi>NP</mi></mrow><mo>⊆</mo><mrow><mi>coNP</mi></mrow><mo>/</mo><mrow><mi>poly</mi></mrow></math></span>.</div></div>\",\"PeriodicalId\":50224,\"journal\":{\"name\":\"Journal of Computer and System Sciences\",\"volume\":\"148 \",\"pages\":\"Article 103599\"},\"PeriodicalIF\":1.1000,\"publicationDate\":\"2024-10-21\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Journal of Computer and System Sciences\",\"FirstCategoryId\":\"94\",\"ListUrlMain\":\"https://www.sciencedirect.com/science/article/pii/S0022000024000941\",\"RegionNum\":3,\"RegionCategory\":\"计算机科学\",\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q1\",\"JCRName\":\"BUSINESS, FINANCE\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Journal of Computer and System Sciences","FirstCategoryId":"94","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S0022000024000941","RegionNum":3,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"BUSINESS, FINANCE","Score":null,"Total":0}
引用次数: 0
摘要
如果 M 的边的端点所诱导的 G 子图是一个森林,那么图 G 中的匹配 M 就是非循环匹配。给定一个图 G 和 ℓ∈N,非循环匹配问 G 是否有大小至少为 ℓ 的非循环匹配。在本文中,我们证明了假设 W[1]⊈FPT 时,不存在任何 FPT 近似算法,可以在以ℓ 为参数时,以常数因子内逼近 Acyclic Matching。我们的还原也证明了诱导匹配和唯一限制匹配的 FPT 近似性。我们还考虑了 Acyclic Matching 的三个低于保证的参数,即 n2-ℓ、MM(G)-ℓ 和 IS(G)-ℓ,其中 n=V(G), MM(G) 是匹配数,IS(G) 是 G 的独立数。此外,我们还证明,除非 NP⊆coNP/poly,否则无循环匹配并不表现出关于顶点覆盖数(或顶点到小块的删除距离)加上匹配大小的多项式内核。
Parameterized results on acyclic matchings with implications for related problems
A matching M in a graph G is an acyclic matching if the subgraph of G induced by the endpoints of the edges of M is a forest. Given a graph G and , Acyclic Matching asks whether G has an acyclic matching of size at least ℓ. In this paper, we prove that assuming , there does not exist any -approximation algorithm for Acyclic Matching that approximates it within a constant factor when parameterized by ℓ. Our reduction also asserts -inapproximability for Induced Matching and Uniquely Restricted Matching. We also consider three below-guarantee parameters for Acyclic Matching, viz. , , and , where , is the matching number, and is the independence number of G. Also, we show that Acyclic Matching does not exhibit a polynomial kernel with respect to vertex cover number (or vertex deletion distance to clique) plus the size of the matching unless .
期刊介绍:
The Journal of Computer and System Sciences publishes original research papers in computer science and related subjects in system science, with attention to the relevant mathematical theory. Applications-oriented papers may also be accepted and they are expected to contain deep analytic evaluation of the proposed solutions.
Research areas include traditional subjects such as:
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• Complexity theory
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