English
Related papers

Related papers: Near-Optimal Directed Low-Diameter Decompositions

200 papers

We present improved algorithms for short cycle decomposition of a graph. Short cycle decompositions were introduced in the recent work of Chu et al, and were used to make progress on several questions in graph sparsification. For all…

Data Structures and Algorithms · Computer Science 2019-01-15 Yang P. Liu , Sushant Sachdeva , Zejun Yu

In this paper we provide a $\tilde{O}(m\sqrt{n})$ time algorithm that computes a $3$-multiplicative approximation of the girth of a $n$-node $m$-edge directed graph with non-negative edge lengths. This is the first algorithm which…

Data Structures and Algorithms · Computer Science 2020-04-15 Shiri Chechik , Yang P. Liu , Omer Rotem , Aaron Sidford

The radius and diameter are fundamental graph parameters. They are defined as the minimum and maximum of the eccentricities in a graph, respectively, where the eccentricity of a vertex is the largest distance from the vertex to another…

Data Structures and Algorithms · Computer Science 2015-06-08 Amir Abboud , Virginia Vassilevska Williams , Joshua Wang

We study dynamic $(1-\epsilon)$-approximate rounding of fractional matchings -- a key ingredient in numerous breakthroughs in the dynamic graph algorithms literature. Our first contribution is a surprisingly simple deterministic rounding…

Data Structures and Algorithms · Computer Science 2024-02-26 Sayan Bhattacharya , Peter Kiss , Aaron Sidford , David Wajc

We obtain faster expander decomposition algorithms for directed graphs, matching the guarantees of Saranurak and Wang (SODA 2019) for expander decomposition on undirected graphs. Our algorithms are faster than prior work and also generalize…

Data Structures and Algorithms · Computer Science 2025-11-11 Henry Fleischmann , George Z. Li , Jason Li

We present near-optimal algorithms for detecting small vertex cuts in the CONGEST model of distributed computing. Despite extensive research in this area, our understanding of the vertex connectivity of a graph is still incomplete,…

Data Structures and Algorithms · Computer Science 2023-06-21 Merav Parter , Asaf Petruschka

We consider the problem of decomposing the edges of a directed graph into as few paths as possible. There is a natural lower bound for the number of paths needed in an edge decomposition of a directed graph $D$ in terms of its degree…

Combinatorics · Mathematics 2021-09-29 Alberto Espuny Díaz , Viresh Patel , Fabian Stroh

We prove that any $n$-node graph $G$ with diameter $D$ admits shortcuts with congestion $O(\delta D \log n)$ and dilation $O(\delta D)$, where $\delta$ is the maximum edge-density of any minor of $G$. Our proof is simple, elementary, and…

Data Structures and Algorithms · Computer Science 2020-08-10 Mohsen Ghaffari , Bernhard Haeupler

We revisit the problem of privately releasing the all-pairs shortest path distances of a weighted undirected graph up to low additive error, which was first studied by Sealfon [Sea16]. In this paper, we improve significantly on Sealfon's…

Data Structures and Algorithms · Computer Science 2022-04-06 Justin Y. Chen , Shyam Narayanan , Yinzhan Xu

We present a deterministic near-linear time algorithm that computes the edge-connectivity and finds a minimum cut for a simple undirected unweighted graph G with n vertices and m edges. This is the first o(mn) time deterministic algorithm…

Data Structures and Algorithms · Computer Science 2018-10-30 Ken-ichi Kawarabayashi , Mikkel Thorup

The girth of a graph, i.e. the length of its shortest cycle, is a fundamental graph parameter. Unfortunately all known algorithms for computing, even approximately, the girth and girth-related structures in directed weighted $m$-edge and…

Data Structures and Algorithms · Computer Science 2018-08-14 Jakub Pachocki , Liam Roditty , Aaron Sidford , Roei Tov , Virginia Vassilevska Williams

We consider the fundamental problems of determining the rooted and global edge and vertex connectivities (and computing the corresponding cuts) in directed graphs. For rooted (and hence also global) edge connectivity with small integer…

Data Structures and Algorithms · Computer Science 2021-04-16 Chandra Chekuri , Kent Quanrud

We study graph connectivity problem in MPC model. On an undirected graph with $n$ nodes and $m$ edges, $O(\log n)$ round connectivity algorithms have been known for over 35 years. However, no algorithms with better complexity bounds were…

Data Structures and Algorithms · Computer Science 2018-05-09 Alexandr Andoni , Clifford Stein , Zhao Song , Zhengyu Wang , Peilin Zhong

We give a fully dynamic algorithm maintaining a $(1-\varepsilon)$-approximate directed densest subgraph in $\tilde{O}(\log^3(n)/\varepsilon^6)$ amortized time or $\tilde{O}(\log^4(n)/\varepsilon^7)$ worst-case time per edge update (where…

Data Structures and Algorithms · Computer Science 2023-12-19 Richard Li , Kent Quanrud

A distributed network is modeled by a graph having $n$ nodes (processors) and diameter $D$. We study the time complexity of approximating {\em weighted} (undirected) shortest paths on distributed networks with a $O(\log n)$ {\em bandwidth…

Data Structures and Algorithms · Computer Science 2014-05-23 Danupon Nanongkai

In many models for large-scale computation, decomposition of the problem is key to efficient algorithms. For distance-related graph problems, it is often crucial that such a decomposition results in clusters of small diameter, while the…

Distributed, Parallel, and Cluster Computing · Computer Science 2019-09-20 Ruben Becker , Yuval Emek , Christoph Lenzen

We study the problem of releasing the weights of all-pair shortest paths in a weighted undirected graph with differential privacy (DP). In this setting, the underlying graph is fixed and two graphs are neighbors if their edge weights differ…

Data Structures and Algorithms · Computer Science 2022-03-31 Badih Ghazi , Ravi Kumar , Pasin Manurangsi , Jelani Nelson

Approximating the graph diameter is a basic task of both theoretical and practical interest. A simple folklore algorithm can output a 2-approximation to the diameter in linear time by running BFS from an arbitrary vertex. It has been open…

Computational Complexity · Computer Science 2021-11-16 Mina Dalirrooyfard , Ray Li , Virginia Vassilevska Williams

In 1996, Karger [Kar96] gave a startling randomized algorithm that finds a minimum-cut in a (weighted) graph in time $O(m\log^3n)$ which he termed near-linear time meaning linear (in the size of the input) times a polylogarthmic factor. In…

Data Structures and Algorithms · Computer Science 2024-01-12 Monika Henzinger , Jason Li , Satish Rao , Di Wang

We study the fully dynamic All-Pairs Shortest Paths (APSP) problem in undirected edge-weighted graphs. Given an $n$-vertex graph $G$ with non-negative edge lengths, that undergoes an online sequence of edge insertions and deletions, the…

Data Structures and Algorithms · Computer Science 2023-04-20 Julia Chuzhoy , Ruimin Zhang