collaborators

6 papers

cs.DS2026

A faster polynomial-space algorithm for Hamiltonian cycle parameterized by treedepth

Stefan Kratsch

A large number of NP-hard graph problems can be solved in time and space when the input graph is provided together with a tree decomposition of width , in many ca…

cs.DS2025

Tight Bounds for Feedback Vertex Set Parameterized by Clique-width

Narek Bojikian, Stefan Kratsch

We introduce a new notion of acyclicity representation in labeled graphs, and present three applications thereof. Our main result is an algorithm that, given a graph and a -…

cs.DS2025

Boundaried Kernelization

Leonid Antipov, Stefan Kratsch

The notion of a (polynomial) kernelization from parameterized complexity is a well-studied model for efficient preprocessing for hard computational problems. By now, it is quite we…

cs.CC2025

Flow-augmentation III: Complexity dichotomy for Boolean CSPs parameterized by the number of unsatisfied constraints

Eun Jung Kim, Stefan Kratsch, Marcin Pilipczuk +1

We study the parameterized problem of satisfying ``almost all'' constraints of a given formula over a fixed, finite Boolean constraint language , with or without weights. M…

cs.DS2025

Tight Bounds for some Classical Problems Parameterized by Cutwidth

Narek Bojikian, Vera Chekan, Stefan Kratsch

Cutwidth is a widely studied parameter that quantifies how well a graph can be decomposed along small edge-cuts. It complements pathwidth, which captures decomposition by small ver…

cs.DS2025

Efficient parameterized approximation

Stefan Kratsch, Pascal Kunz

Many problems are NP-hard and, unless P = NP, do not admit polynomial-time exact algorithms. The fastest known exact algorithms exactly usually take time exponential in the input s…