English
Related papers

Related papers: Optimum-width upward drawings of trees

200 papers

For finite graphs, path-width is an interesting and useful concept, but if we extend it to infinite graphs in the most obvious way (by making the indexing path infinite), it does not work nicely. The simplest extension that works nicely is…

Combinatorics · Mathematics 2025-09-23 Tung Nguyen , Alex Scott , Paul Seymour

We introduce top trees as a design of a new simpler interface for data structures maintaining information in a fully-dynamic forest. We demonstrate how easy and versatile they are to use on a host of different applications. For example, we…

Data Structures and Algorithms · Computer Science 2007-05-23 Stephen Alstrup , Jacob Holm , Kristian de Lichtenberg , Mikkel Thorup

The Wiener index is maximized over the set of trees with the given vertex weight and degree sequences. This model covers the traditional "unweighed" Wiener index, the terminal Wiener index, and the vertex distance index. It is shown that…

Combinatorics · Mathematics 2017-05-12 Mikhail Goubko

We provide an algorithm for computing a planar morph between any two planar straight-line drawings of any $n$-vertex plane graph in $O(n)$ morphing steps, thus improving upon the previously best known $O(n^2)$ upper bound. Further, we prove…

Data Structures and Algorithms · Computer Science 2014-02-20 Patrizio Angelini , Giordano Da Lozzo , Giuseppe Di Battista , Fabrizio Frati , Maurizio Patrignani , Vincenzo Roselli

In this paper we describe a randomized algorithm which returns a maximal spanning forest of an unknown {\em weighted} undirected graph making $O(n)$ $\mathsf{CUT}$ queries in expectation. For weighted graphs, this is optimal due to a result…

Data Structures and Algorithms · Computer Science 2023-06-21 Hang Liao , Deeparnab Chakrabarty

We consider the minimum spanning tree problem with predictions, using the weight-arrival model, i.e., the graph is given, together with predictions for the weights of all edges. Then the actual weights arrive one at a time and an…

Data Structures and Algorithms · Computer Science 2023-02-24 Magnus Berg , Joan Boyar , Lene M. Favrholdt , Kim S. Larsen

We study the problem of low-stretch spanning trees in graphs of bounded width: bandwidth, cutwidth, and treewidth. We show that any simple connected graph $G$ with a linear arrangement of bandwidth $b$ can be embedded into a distribution…

Data Structures and Algorithms · Computer Science 2020-04-20 Glencora Borradaile , Erin Wolf Chambers , David Eppstein , William Maxwell , Amir Nayyeri

A graph is rectilinear planar if it admits a planar orthogonal drawing without bends. While testing rectilinear planarity is NP-hard in general (Garg and Tamassia, 2001), it is a long-standing open problem to establish a tight upper bound…

Data Structures and Algorithms · Computer Science 2023-06-23 Walter Didimo , Michael Kaufmann , Giuseppe Liotta , Giacomo Ortali

We study the space complexity of sketching cuts and Laplacian quadratic forms of graphs. We show that any data structure which approximately stores the sizes of all cuts in an undirected graph on $n$ vertices up to a $1+\epsilon$ error must…

Data Structures and Algorithms · Computer Science 2018-01-01 Charles Carlson , Alexandra Kolla , Nikhil Srivastava , Luca Trevisan

Let $L$ be a set of $n$ lines in the plane, not necessarily in general position. We present an efficient algorithm for finding all the vertices of the arrangement $A(L)$ of maximum level, where the level of a vertex $v$ is the number of…

Computational Geometry · Computer Science 2020-03-03 Dan Halperin , Sariel Har-Peled , Kurt Mehlhorn , Eunjin Oh , Micha Sharir

Topological drawings are representations of graphs in the plane, where vertices are represented by points, and edges by simple curves connecting the points. A drawing is simple if two edges intersect at most in a single point, either at a…

Computational Geometry · Computer Science 2022-09-08 Alfredo García , Alexander Pilz , Javier Tejel

Expander graphs are known to be robust to edge deletions in the following sense: for any online sequence of edge deletions $e_1, e_2, \ldots, e_k$ to an $m$-edge graph $G$ that is initially a $\phi$-expander, the algorithm can grow a set $P…

Data Structures and Algorithms · Computer Science 2025-04-02 Simon Meierhans , Maximilian Probst Gutenberg , Thatchaphol Saranurak

Learning a regression function using censored or interval-valued output data is an important problem in fields such as genomics and medicine. The goal is to learn a real-valued prediction function, and the training output labels indicate an…

Machine Learning · Statistics 2017-10-30 Alexandre Drouin , Toby Dylan Hocking , François Laviolette

We investigate the structure of trees that have greatest maximum eigenvalue among all trees with a given degree sequence. We show that in such an extremal tree the degree sequence is non-increasing with respect to an ordering of the…

Combinatorics · Mathematics 2008-04-18 Tuerker Biyikoglu , Marc Hellmuth , Josef Leydold

Short spanning trees subject to additional constraints are important building blocks in various approximation algorithms. Especially in the context of the Traveling Salesman Problem (TSP), new techniques for finding spanning trees with…

Data Structures and Algorithms · Computer Science 2023-09-13 Martin Nägele , Rico Zenklusen

We give alternative definitions for maximum matching width, e.g. a graph $G$ has $\operatorname{mmw}(G) \leq k$ if and only if it is a subgraph of a chordal graph $H$ and for every maximal clique $X$ of $H$ there exists $A,B,C \subseteq X$…

Data Structures and Algorithms · Computer Science 2015-07-10 Jisu Jeong , Sigve Hortemo Sæther , Jan Arne Telle

Codes over trees were introduced recently to bridge graph theory and coding theory with diverse applications in computer science and beyond. A central challenge lies in determining the maximum number of labelled trees over $n$ nodes with…

Combinatorics · Mathematics 2025-04-10 Yanzhi Li , Wenjie Zhong , Tingting Chen , Xiande Zhang

Many hard algorithmic problems dealing with graphs, circuits, formulas and constraints admit polynomial-time upper bounds if the underlying graph has small treewidth. The same problems often encourage reducing the maximal degree of vertices…

Discrete Mathematics · Computer Science 2011-11-04 Igor Markov , Yaoyun Shi

In phylogenetic networks, it is desirable to estimate edge lengths in substitutions per site or calendar time. Yet, there is a lack of scalable methods that provide such estimates. Here we consider the problem of obtaining edge length…

Populations and Evolution · Quantitative Biology 2024-08-06 Jingcheng Xu , Cécile Ané

The Subtree Isomorphism problem asks whether a given tree is contained in another given tree. The problem is of fundamental importance and has been studied since the 1960s. For some variants, e.g., ordered trees, near-linear time algorithms…

Computational Complexity · Computer Science 2015-10-16 Amir Abboud , Arturs Backurs , Thomas Dueholm Hansen , Virginia Vassilevska Williams , Or Zamir