English
Related papers

Related papers: Coloring problem of signed interval graphs

200 papers

A natural way of increasing our understanding of NP-complete graph problems is to restrict the input to a special graph class. Classes of $H$-free graphs, that is, graphs that do not contain some graph $H$ as an induced subgraph, have…

Data Structures and Algorithms · Computer Science 2022-04-19 Christoph Brause , Petr Golovach , Barnaby Martin , Daniël Paulusma , Siani Smith

We study reconfiguration problems for cliques in a graph, which determine whether there exists a sequence of cliques that transforms a given clique into another one in a step-by-step fashion. As one step of a transformation, we consider…

Data Structures and Algorithms · Computer Science 2014-12-15 Takehiro Ito , Hirotaka Ono , Yota Otachi

The NP-complete problems Colouring and k-Colouring $(k\geq 3$) are well studied on $H$-free graphs, i.e., graphs that do not contain some fixed graph $H$ as an induced subgraph. We research to what extent the known polynomial-time…

Data Structures and Algorithms · Computer Science 2025-12-30 Daniël Paulusma , Johannes Rauch , Erik Jan van Leeuwen

In this paper, we introduce a class of graphs which we call average hereditary graphs. Many graphs that occur in the usual graph theory applications belong to this class of graphs. Many popular types of graphs fall under this class, such as…

Discrete Mathematics · Computer Science 2025-08-11 Syed Mujtaba Hassan , Shahid Hussain

An equitable coloring of a graph $G=(V,E)$ is a (proper) vertex-coloring of $G$, such that the sizes of any two color classes differ by at most one. In this paper, we consider the equitable coloring problem in block graphs. Recall that the…

Discrete Mathematics · Computer Science 2024-02-14 Hanna Furmańczyk , Vahan Mkrtchyan

The generic homomorphism problem, which asks whether an input graph $G$ admits a homomorphism into a fixed target graph $H$, has been widely studied in the literature. In this article, we provide a fine-grained complexity classification of…

Computational Complexity · Computer Science 2022-10-14 Robert Ganian , Thekla Hamm , Viktoriia Korchemna , Karolina Okrasa , Kirill Simonov

Many NP-complete graph problems are polynomial-time solvable on graph classes of bounded clique-width. Several of these problems are polynomial-time solvable on a hereditary graph class ${\cal G}$ if they are so on the atoms (graphs with no…

Discrete Mathematics · Computer Science 2026-02-19 Konrad K. Dabrowski , Tomáš Masařík , Jana Novotná , Daniël Paulusma , Paweł Rzążewski

In the Coloured Clustering problem, we wish to colour vertices of an edge coloured graph to produce as many stable edges as possible, i.e., edges with the same colour as their ends. In this paper, we reveal that the problem is in fact a…

Data Structures and Algorithms · Computer Science 2018-07-30 Leizhen CAI , On Yin LEUNG

The $k$-Coloring problem on hereditary graph classes has been a deeply researched problem over the last decade. A hereditary graph class is characterized by a (possibly infinite) list of minimal forbidden induced subgraphs. We say that a…

Computational Complexity · Computer Science 2025-09-03 Justyna Jaworska , Bartłomiej Kielak , Tomáš Masařík , Jana Masaříková

This paper describes several new problems and ideas concerning algebraic geometry and complexity theory. It first uses the idea of coloring graphs with elements of finite fields. This procedure then shows that graph coloring problems can be…

Algebraic Geometry · Mathematics 2025-03-20 Paul Hriljac

The oriented chromatic polynomial of a oriented graph outputs the number of oriented $k$-colourings for any input $k$. We fully classify those oriented graphs for which the oriented graph has the same chromatic polynomial as the underlying…

Discrete Mathematics · Computer Science 2018-12-24 Danielle Cox , Christopher Duffy

For a graph $F$, a graph $G$ is \emph{$F$-free} if it does not contain an induced subgraph isomorphic to $F$. For two graphs $G$ and $H$, an \emph{$H$-coloring} of $G$ is a mapping $f:V(G)\rightarrow V(H)$ such that for every edge $uv\in…

Data Structures and Algorithms · Computer Science 2023-03-06 Maria Chudnovsky , Shenwei Huang , Paweł Rzążewski , Sophie Spirkl , Mingxian Zhong

Ray intersection graphs are intersection graphs of rays, or halflines, in the plane. We show that any planar graph has an even subdivision whose complement is a ray intersection graph. The construction can be done in polynomial time and…

Computational Geometry · Computer Science 2011-11-28 Sergio Cabello , Jean Cardinal , Stefan Langerman

An edge-coloring of a graph $G$ with colors $1,2,\ldots,t$ is called an interval $t$-coloring if for each $i\in \{1,2,\ldots,t\}$ there is at least one edge of $G$ colored by $i$, and the colors of edges incident to any vertex of $G$ are…

Discrete Mathematics · Computer Science 2010-08-13 R. R. Kamalian , P. A. Petrosyan

A $k$-colouring (not necessarily proper) of vertices of a graph is called {\it acyclic}, if for every pair of distinct colours $i$ and $j$ the subgraph induced by the edges whose endpoints have colours $i$ and $j$ is acyclic. In the paper…

Discrete Mathematics · Computer Science 2016-08-24 Anna Fiedorowicz , Elżbieta Sidorowicz

Graph parameters such as the clique number, the chromatic number, and the independence number are central in many areas, ranging from computer networks to linguistics to computational neuroscience to social networks. In particular, the…

Computational Complexity · Computer Science 2020-12-15 Fabian Frei , Edith Hemaspaandra , Jörg Rothe

A clique of a graph is a maximal set of vertices of size at least 2 that induces a complete graph. A $k$-clique-colouring of a graph is a colouring of the vertices with at most $k$ colours such that no clique is monochromatic. D\'efossez…

Computational Complexity · Computer Science 2013-12-12 Hélio B. Macêdo Filho , Raphael C. S. Machado , Celina M. H. de Figueiredo

The generalized list $T$-coloring is a common generalization of many graph coloring models, including classical coloring, $L(p,q)$-labeling, channel assignment and $T$-coloring. Every vertex from the input graph has a list of permitted…

Discrete Mathematics · Computer Science 2013-12-04 Konstanty Junosza-Szaniawski , Paweł Rzążewski

A b-coloring of the vertices of a graph is a proper coloring where each color class contains a vertex which is adjacent to at least one vertex in each other color class. The b-chromatic number of $G$ is the maximum integer $b(G)$ for which…

Discrete Mathematics · Computer Science 2015-11-18 Victor Campos , Ana Silva

A rainbow colouring of a connected graph is a colouring of the edges of the graph, such that every pair of vertices is connected by at least one path in which no two edges are coloured the same. Such a colouring using minimum possible…

Discrete Mathematics · Computer Science 2012-05-09 L. Sunil Chandran , Deepak Rajendraprasad