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Related papers: Spanners of Complete $k$-Partite Geometric Graphs

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A $k$-star is a complete bipartite graph $K_{1,k}$. A partial $k$-star design of order $n$ is a pair $(V,\mathcal{A})$ where $V$ is a set of $n$ vertices and $\mathcal{A}$ is a set of edge-disjoint $k$-stars whose vertex sets are subsets of…

Combinatorics · Mathematics 2025-08-19 Ajani De Vas Gunasekara , Daniel Horsley

A multiplicative $\alpha$-spanner $H$ is a subgraph of $G=(V,E)$ with the same vertices and fewer edges that preserves distances up to the factor $\alpha$, i.e., $d_H(u,v)\leq\alpha\cdot d_G(u,v)$ for all vertices $u$, $v$. While many…

Data Structures and Algorithms · Computer Science 2021-07-06 Markus Chimani , Finn Stutzenstein

A graph spanner is a fundamental graph structure that faithfully preserves the pairwise distances in the input graph up to a small multiplicative stretch. The common objective in the computation of spanners is to achieve the best-known…

Data Structures and Algorithms · Computer Science 2019-02-25 Merav Parter , Ronitt Rubinfeld , Ali Vakilian , Anak Yodpinyanee

A graph separator is a subset of vertices of a graph whose removal divides the graph into small components. Computing small graph separators for various classes of graphs is an important computational task. In this paper, we present a…

Computational Complexity · Computer Science 2020-05-14 Chetan Gupta , Rahul Jain , Raghunath Tewari

We present a $(1+\frac{k}{k+2})$-approximation algorithm for the Maximum $k$-dependent Set problem on bipartite graphs for any $k\ge1$. For a graph with $n$ vertices and $m$ edges, the algorithm runs in $O(k m \sqrt{n})$ time and improves…

Combinatorics · Mathematics 2021-10-07 Seyedmohammadhossein Hosseinian , Sergiy Butenko

Spanner constructions focus on the initial design of the network. However, networks tend to improve over time. In this paper, we focus on the improvement step. Given a graph and a budget $k$, which $k$ edges do we add to the graph to…

Computational Geometry · Computer Science 2024-07-08 Kevin Buchin , Maike Buchin , Joachim Gudmundsson , Sampson Wong

A $t$-spanner of a graph is a subgraph that $t$-approximates pairwise distances. The greedy algorithm is one of the simplest and most well-studied algorithms for constructing a sparse spanner: it computes a $t$-spanner with $n^{1+O(1/t)}$…

Data Structures and Algorithms · Computer Science 2023-08-03 Bernhard Haeupler , D Ellis Hershkowitz , Zihan Tan

In the Split Vertex Deletion problem, given a graph G and an integer k, we ask whether one can delete k vertices from the graph G to obtain a split graph (i.e., a graph, whose vertex set can be partitioned into two sets: one inducing a…

Data Structures and Algorithms · Computer Science 2012-08-07 Marek Cygan , Marcin Pilipczuk

Constructing a sparse spanning subgraph is a fundamental primitive in graph theory. In this paper, we study this problem in the Centralized Local model, where the goal is to decide whether an edge is part of the spanning subgraph by…

Data Structures and Algorithms · Computer Science 2017-07-20 Christoph Lenzen , Reut Levi

A $t$-spanner of a graph $G$ is a subgraph $H$ in which all distances are preserved up to a multiplicative $t$ factor. A classical result of Alth\"ofer et al. is that for every integer $k$ and every graph $G$, there is a $(2k-1)$-spanner of…

Data Structures and Algorithms · Computer Science 2019-03-19 Eden Chlamtáč , Michael Dinitz , Thomas Robinson

Given a point set $P$ in a metric space and a real number $t \geq 1$, an \emph{oriented $t$-spanner} is an oriented graph $\overrightarrow{G}=(P,\overrightarrow{E})$, where for every pair of distinct points $p$ and $q$ in $P$, the shortest…

Computational Geometry · Computer Science 2024-12-12 Kevin Buchin , Antonia Kalb , Anil Maheshwari , Saeed Odak , Michiel Smid , Carolin Rehs , Sampson Wong

A $k$-spanner of a graph $G$ is a sparse subgraph that preserves its shortest path distances up to a multiplicative stretch factor of $k$, and a $k$-emulator is similar but not required to be a subgraph of $G$. A classic theorem by Thorup…

Data Structures and Algorithms · Computer Science 2021-11-22 Greg Bodwin , Michael Dinitz , Yasamin Nazari

We consider the Minimum Steiner Cut problem on undirected planar graphs with non-negative edge weights. This problem involves finding the minimum cut of the graph that separates a specified subset $X$ of vertices (terminals) into two parts.…

Data Structures and Algorithms · Computer Science 2020-01-01 Stephen Jue , Philip N. Klein

Coudert et al. (SODA'18) proved that under the Strong Exponential-Time Hypothesis, for any $\epsilon >0$, there is no ${\cal O}(2^{o(k)}n^{2-\epsilon})$-time algorithm for computing the diameter within the $n$-vertex cubic graphs of…

Data Structures and Algorithms · Computer Science 2020-11-18 Guillaume Ducoffe

A temporal graph is an undirected graph $G=(V,E)$ along with a function that assigns a time-label to each edge in $E$. A path in $G$ with non-decreasing time-labels is called temporal path and the distance from $u$ to $v$ is the minimum…

Data Structures and Algorithms · Computer Science 2022-06-23 Davide Bilò , Gianlorenzo D'Angelo , Luciano Gualà , Stefano Leucci , Mirko Rossi

The greedy algorithm adapted from Kruskal's algorithm is an efficient and folklore way to produce a $k$-spanner with girth at least $k+2$. The greedy algorithm has shown to be `existentially optimal', while it's not `universally optimal'…

Data Structures and Algorithms · Computer Science 2024-11-05 Yeyuan Chen

We devise an algorithm that approximately computes the number of paths of length $k$ in a given directed graph with $n$ vertices up to a multiplicative error of $1 \pm \varepsilon$. Our algorithm runs in time $\varepsilon^{-2} 4^k(n+m)…

Data Structures and Algorithms · Computer Science 2018-04-26 Cornelius Brand , Holger Dell , Thore Husfeldt

We consider problems of the following type: given a graph $G$, how many edges are needed in the worst case for a sparse subgraph $H$ that approximately preserves distances between a given set of node pairs $P$? Examples include pairwise…

Data Structures and Algorithms · Computer Science 2021-05-10 Greg Bodwin

The diameter of a graph is one if its most important parameters, being used in many real-word applications. In particular, the diameter dictates how fast information can spread throughout data and communication networks. Thus, it is a…

Data Structures and Algorithms · Computer Science 2019-02-21 Keerti Choudhary , Omer Gold

In a geometric graph, $G$, the \emph{stretch factor} between two vertices, $u$ and $w$, is the ratio between the Euclidean length of the shortest path from $u$ to $w$ in $G$ and the Euclidean distance between $u$ and $w$. The \emph{average…

Computational Geometry · Computer Science 2013-12-02 Vida Dujmovic , Pat Morin , Michiel Smid