activity
20192024
collaborators

9 papers

math.CO2024

Backbone coloring for graphs with degree 4

Krzysztof Michalik, Krzysztof Turowski

The -backbone coloring of the graph with backbone is a graph-coloring problem in which we are given a graph and a subgraph , and we want to assign colors to verti…

math.CO2023

Edge coloring of products of signed graphs

Robert Janczewski, Krzysztof Turowski, Bartłomiej Wróblewski

In 2020, Behr defined the problem of edge coloring of signed graphs and showed that every signed graph can be colored using exactly or colors, where $Δ(G…

cs.DM2023

On the concentration of the maximum degree in the duplication-divergence models

Alan Frieze, Krzysztof Turowski, Wojciech Szpankowski

We present a rigorous and precise analysis of the maximum degree and the average degree in a dynamic duplication-divergence graph model introduced by Solé, Pastor-Satorras et al. i…

math.CO2023

The Game Chromatic Number of Complete Multipartite Graphs

Paweł Obszarski, Krzysztof Turowski, Hubert Zięba

In this paper we investigate the game chromatic number for complete multipartite graphs. Our results consist of two findings: (1) building on Dunn's strategies for equal-sized part…

cs.DM2022

Approximation algorithms for job scheduling with block-type conflict graphs

Hanna Furmańczyk, Tytus Pikies, Inka Sokołowska +1

The problem of scheduling jobs on parallel machines (identical, uniform, or unrelated), under incompatibility relation modeled as a block graph, under the makespan optimality crite…

cs.DM2022

Edge coloring of graphs of signed class 1 and 2

Robert Janczewski, Krzysztof Turowski, Bartłomiej Wróblewski

Recently, Behr introduced a notion of the chromatic index of signed graphs and proved that for every signed graph , it holds that \[ Δ(G)\leqχ'(G\text{, }σ)\leqΔ(G)+1\text…

cs.DM2021

On λ-backbone coloring of cliques with tree backbones in linear time

Krzysztof Michalik, Krzysztof Turowski

A -backbone coloring of a graph with its subgraph (also called a backbone) is a function ensuring that is a proper colorin…

cs.DS2020

Scheduling with Complete Multipartite Incompatibility Graph on Parallel Machines

Tytus Pikies, Krzysztof Turowski, Marek Kubale

In this paper we consider the problem of scheduling on parallel machines with a presence of incompatibilities between jobs. The incompatibility relation can be modeled as a complet…

cs.SI2019

Temporal Ordered Clustering in Dynamic Networks: Unsupervised and Semi-supervised Learning Algorithms

Krzysztof Turowski, Jithin K. Sreedharan, Wojciech Szpankowski

In temporal ordered clustering, given a single snapshot of a dynamic network in which nodes arrive at distinct time instants, we aim at partitioning its nodes into ordered clus…