Koki Shinraku, Katsuhisa Yamanaka, Takashi Hirayama
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In this paper, we consider the problem of enumerating all the rectangular duals of a given irreducible triangulation. It is known that the set of rectangular duals of an irreducible triangulation <span><math><mi>T</mi></math></span> one-to-one corresponds to the set of transversal edge-partitions of <span><math><mi>T</mi></math></span>. Hence, in this paper, we design an enumeration algorithm of all the transversal edge-partitions of an irreducible triangulation with <span><math><mi>n</mi></math></span> vertices. The proposed algorithm enumerates them in <span><math><mrow><mi>O</mi><mrow><mo>(</mo><mi>n</mi><mo>)</mo></mrow></mrow></math></span>-delay and <span><math><mrow><mi>O</mi><mrow><mo>(</mo><msup><mrow><mi>n</mi></mrow><mrow><mn>2</mn></mrow></msup><mo>)</mo></mrow></mrow></math></span>-space after <span><math><mrow><mi>O</mi><mrow><mo>(</mo><mi>n</mi><mo>log</mo><mi>n</mi><mo>)</mo></mrow></mrow></math></span>-time preprocessing.</div></div>","PeriodicalId":50573,"journal":{"name":"Discrete Applied Mathematics","volume":"361 ","pages":"Pages 276-287"},"PeriodicalIF":1.0000,"publicationDate":"2024-11-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"Efficient enumeration of transversal edge-partitions\",\"authors\":\"Koki Shinraku, Katsuhisa Yamanaka, Takashi Hirayama\",\"doi\":\"10.1016/j.dam.2024.10.016\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<div><div>An irreducible triangulation is a plane graph such that its outer face is a quadrangle, every inner face is a triangle, and it has no separating triangle. Let <span><math><mi>T</mi></math></span> be an irreducible triangulation with <span><math><mi>n</mi></math></span> vertices. A rectangular dual <span><math><mi>R</mi></math></span> of <span><math><mi>T</mi></math></span> is a dissection of a rectangle into (small) rectangles such that (1) each rectangle of <span><math><mi>R</mi></math></span> corresponds to a vertex of <span><math><mi>T</mi></math></span>, and (2) two rectangles of <span><math><mi>R</mi></math></span> are adjacent if the two corresponding vertices of <span><math><mi>T</mi></math></span> are adjacent. Finding a rectangular dual of a given graph has an application on cartograms and VLSI floor-planning. In this paper, we consider the problem of enumerating all the rectangular duals of a given irreducible triangulation. It is known that the set of rectangular duals of an irreducible triangulation <span><math><mi>T</mi></math></span> one-to-one corresponds to the set of transversal edge-partitions of <span><math><mi>T</mi></math></span>. Hence, in this paper, we design an enumeration algorithm of all the transversal edge-partitions of an irreducible triangulation with <span><math><mi>n</mi></math></span> vertices. 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引用次数: 0
摘要
不可还原三角形是这样一个平面图形:它的外侧面是一个四边形,每个内侧面都是一个三角形,并且没有分离三角形。设 T 是一个有 n 个顶点的不可还原三角形。T 的矩形对偶 R 是将矩形分割成(小)矩形,这样 (1) R 的每个矩形都对应 T 的一个顶点;(2) 如果 T 的两个对应顶点相邻,则 R 的两个矩形相邻。寻找给定图形的矩形对偶可应用于制图和超大规模集成电路平面规划。在本文中,我们考虑的问题是枚举给定不可还原三角形的所有矩形对偶。众所周知,不可还原三角形 T 的矩形对偶集一一对应于 T 的横向边分区集。因此,在本文中,我们设计了一种枚举具有 n 个顶点的不可还原三角形的所有横向边分区的算法。经过 O(nlogn)-time 的预处理后,所提出的算法能在 O(n)-delay 和 O(n2)-space 内枚举出它们。
Efficient enumeration of transversal edge-partitions
An irreducible triangulation is a plane graph such that its outer face is a quadrangle, every inner face is a triangle, and it has no separating triangle. Let be an irreducible triangulation with vertices. A rectangular dual of is a dissection of a rectangle into (small) rectangles such that (1) each rectangle of corresponds to a vertex of , and (2) two rectangles of are adjacent if the two corresponding vertices of are adjacent. Finding a rectangular dual of a given graph has an application on cartograms and VLSI floor-planning. In this paper, we consider the problem of enumerating all the rectangular duals of a given irreducible triangulation. It is known that the set of rectangular duals of an irreducible triangulation one-to-one corresponds to the set of transversal edge-partitions of . Hence, in this paper, we design an enumeration algorithm of all the transversal edge-partitions of an irreducible triangulation with vertices. The proposed algorithm enumerates them in -delay and -space after -time preprocessing.
期刊介绍:
The aim of Discrete Applied Mathematics is to bring together research papers in different areas of algorithmic and applicable discrete mathematics as well as applications of combinatorial mathematics to informatics and various areas of science and technology. Contributions presented to the journal can be research papers, short notes, surveys, and possibly research problems. The "Communications" section will be devoted to the fastest possible publication of recent research results that are checked and recommended for publication by a member of the Editorial Board. The journal will also publish a limited number of book announcements as well as proceedings of conferences. These proceedings will be fully refereed and adhere to the normal standards of the journal.
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