Publications associées à Graphe birégulier

A Distributed Augmenting Path Approach for the Bottleneck Assignment Problem

We develop an algorithm to solve the bottleneck assignment problem (BAP) that is amenable to having computation distributed over a network of agents. This consists of exploring how each component of the algorithm can be distributed, with a focus on one com ...

Ieee-Inst Electrical Electronics Engineers Inc2024

Improved Ramsey-type results for comparability graphs

Istvan Tomon, Dániel József Korándi

Several discrete geometry problems are equivalent to estimating the size of the largest homogeneous sets in graphs that happen to be the union of few comparability graphs. An important observation for such results is that if G is an n-vertex graph that is ...

CAMBRIDGE UNIV PRESS2020

Construction of Polar Codes With Sublinear Complexity

Rüdiger Urbanke, Seyed Hamed Hassani, Marco Mondelli

Consider the problem of constructing a polar code of block length N for a given transmission channel W. Previous approaches require one to compute the reliability of the N synthetic channels and then use only those that are sufficiently reliable. However, ...

IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC2019

Tight Bounds for Online Edge Coloring

David Wajc

Vizing's celebrated theorem asserts that any graph of maximum degree Delta admits an edge coloring using at most Delta + 1 colors. In contrast, Bar-Noy, Motwani and Naor showed over a quarter century ago that the trivial greedy algorithm, which uses 2 Delt ...

IEEE COMPUTER SOC2019

Analysis of a Canonical Labeling Algorithm for the Alignment of Correlated Erdős-Rényi Graphs

Matthias Grossglauser, Negar Kiyavash, Osman Emre Dai

Graph alignment in two correlated random graphs refers to the task of identifying the correspondence between vertex sets of the graphs. Recent results have characterized the exact information-theoretic threshold for graph alignment in correlated Erdös-Rény ...

Association for Computing Machinery (ACM)2019

Generalized Turan problems for disjoint copies of graphs

Abhishek Methuku

Given two graphs H and F, the maximum possible number of copies of H in an F-free graph on n vertices is denoted by ex(n, H, F). We investigate the function ex(n, H, kF), where kF denotes k vertex disjoint copies of a fixed graph F. Our results include cas ...

Elsevier2019

Online Matching with General Arrivals

Ola Nils Anders Svensson, Mikhail Kapralov, Buddhima Ruwanmini Gamlath Gamlath Ralalage, Andreas Maggiori, David Wajc

The online matching problem was introduced by Karp, Vazirani and Vazirani nearly three decades ago. In that seminal work, they studied this problem in bipartite graphs with vertices arriving only on one side, and presented optimal deterministic and randomi ...

IEEE COMPUTER SOC2019

New Graph Algorithms via Polyhedral Techniques

Jakub Tarnawski

In this thesis we give new algorithms for two fundamental graph problems. We develop novel ways of using linear programming formulations, even exponential-sized ones, to extract structure from problem instances and to guide algorithms in making progress. S ...

EPFL2019

Ordered Graphs And Large Bi-Cliques In Intersection Graphs Of Curves

János Pach, Istvan Tomon

An ordered graph G(

COMENIUS UNIV2019

Ordered graphs and large bi-cliques in intersection graphs of curves

János Pach, Istvan Tomon

An ordered graph G(

ACADEMIC PRESS LTD- ELSEVIER SCIENCE LTD2019

Weighted Matchings via Unweighted Augmentations

Ola Nils Anders Svensson, Slobodan Mitrovic, Buddhima Ruwanmini Gamlath Gamlath Ralalage

We design a generic method to reduce the task of finding weighted matchings to that of finding short augmenting paths in unweighted graphs. This method enables us to provide efficient implementations for approximating weighted matchings in the massively pa ...

ASSOC COMPUTING MACHINERY2019

Finding Perfect Matchings in Bipartite Hypergraphs

Chidambaram Annamalai

Haxell's condition [14] is a natural hypergraph analog of Hall's condition, which is a well-known necessary and sufficient condition for a bipartite graph to admit a perfect matching. That is, when Haxell's condition holds it forces the existence of a perf ...

SPRINGER HEIDELBERG2018

On some problems related to 2-level polytopes

Manuel Francesco Aprile

In this thesis we investigate a number of problems related to 2-level polytopes, in particular from the point of view of the combinatorial structure and the extension complexity. 2-level polytopes were introduced as a generalization of stable set polytopes ...

EPFL2018

Extension complexity of stable set polytopes of bipartite graphs

Yuri Faenza, Manuel Francesco Aprile

The extension complexity xc(P) of a polytope P is the minimum number of facets of a polytope that affinely projects to P. Let G be a bipartite graph with n vertices, m edges, and no isolated vertices. Let STAB(G) be the convex hull of the stable sets of G. ...

Springer2017

A semi-algebraic version of Zarankiewicz's problem

János Pach

A bipartite graph G is semi-algebraic in R-d if its vertices are represented by point sets P,Q subset of R-d and its edges are defined as pairs of points (p,q) epsilon P x Q that satisfy a Boolean combination of a fixed number of polynomial equations and i ...

European Mathematical Soc2017

Method for determining the walsh-hadamard transform of n samples of a signal and apparatus for performing the same

Martin Vetterli, Robin Scheibler, Saeid Haghighatshoar

A computer-implemented method for determining the Walsh-Hadamard transform of N samples of a signal, comprises electing a plurality of hashing C matrices Σ1, . . . ΣC, computing C hashes of a particular length based at least on a hashing front end and the ...

2015

A Fast Hadamard Transform for Signals with Sub-linear Sparsity in the Transform Domain

Martin Vetterli, Robin Scheibler, Saeid Haghighatshoar

In this paper, we design a new iterative low-complexity algorithm for computing the Walsh-Hadamard transform (WHT) of an N dimensional signal with a K-sparse WHT. We suppose that N is a power of two and K = O(N^α), scales sub-linearly in N for some α ∈ (0, ...

Institute of Electrical and Electronics Engineers2015

On some coloring problems in grids

Dominique de Werra

We study complexity issues related to some coloring problems in grids: we examine in particular the case of List coloring, of Precoloring extension and of (p, q)-List coloring, the case of List coloring in bipartite graphs where lists in the first part of ...

2013

d-Transversals of stable sets and vertex covers in weighted bipartite graphs

Dominique de Werra, Bernard Ries

Let G=(V,E)G=(V,E) be a graph in which every vertex v∈Vv∈V has a weight w(v)⩾0w(v)⩾0 and a cost c(v)⩾0c(v)⩾0. Let SGSG be the family of all maximum-weight stable sets in G . For any integer d⩾0d⩾0, a minimum d-transversal in the graph G with respect to SGS ...

2012

Blockers and transversals in some subclasses of bipartite graphs: When caterpillars are dancing on a grid

Dominique de Werra, Bernard Ries

Given an undirected graph G = (V, E) with matching number nu(G), a d-blocker is a subset of edges B such that nu((V, E \ B))

Elsevier2010