A tight approximation algorithm for the cluster vertex deletion problem

M Aprile, M Drescher, S Fiorini, T Huynh - Mathematical Programming, 2023 - Springer
We give the first 2-approximation algorithm for the cluster vertex deletion problem. This
approximation factor is tight, since approximating the problem within any constant factor …

Subquadratic Kernels for Implicit 3-Hitting Set and 3-Set Packing Problems

FV Fomin, TN Le, D Lokshtanov, S Saurabh… - ACM Transactions on …, 2019 - dl.acm.org
We consider four well-studied NP-complete packing/covering problems on graphs:
Feedback Vertex Set in Tournaments (FVST), Cluster Vertex Deletion (CVD), Triangle …

Expansion Lemma—Variations and Applications to Polynomial-Time Preprocessing

A Jacob, D Majumdar, V Raman - Algorithms, 2023 - mdpi.com
In parameterized complexity, it is well-known that a parameterized problem is fixed-
parameter tractable if and only if it has a kernel—an instance equivalent to the input …

Kernelization for graph packing problems via rainbow matching

S Bessy, M Bougeret, DM Thilikos… - Proceedings of the 2023 …, 2023 - SIAM
We introduce a new kernelization tool, called rainbow matching technique, that is
appropriate for the design of polynomial kernels for packing problems. Our technique …

2-approximating feedback vertex set in tournaments

D Lokshtanov, P Misra, J Mukherjee… - ACM Transactions on …, 2021 - dl.acm.org
A tournament is a directed graph T such that every pair of vertices is connected by an arc. A
feedback vertex set is a set S of vertices in T such that T− S is acyclic. We consider the …

Tournaments and semicomplete digraphs

J Bang-Jensen, F Havet - Classes of directed graphs, 2018 - Springer
The class of tournaments is by far the most well-studied class of digraphs with many deep
and important results. Since Moon's pioneering book in 1968 [146], the study of tournaments …

Improved approximation algorithms for hitting 3-vertex paths

S Fiorini, G Joret, O Schaudt - Mathematical Programming, 2020 - Springer
We study the problem of deleting a minimum cost set of vertices from a given vertex-
weighted graph in such a way that the resulting graph has no induced path on three vertices …

Subquadratic Kernels for Implicit 3-Hitting Set and 3-Set Packing Problems

TN Le, D Lokshtanov, S Saurabh, S Thomassé… - Proceedings of the …, 2018 - SIAM
We consider four well-studied NP-complete packing/covering problems on graphs:
Feedback Vertex Set in Tournaments (FVST), Cluster Vertex Deletion (CVD), Triangle …

Dynamic thresholding search for the feedback vertex set problem

W Sun, JK Hao, Z Wu, W Li, Q Wu - PeerJ Computer Science, 2023 - peerj.com
Given a directed graph G=(V, E), a feedback vertex set is a vertex subset C whose removal
makes the graph G acyclic. The feedback vertex set problem is to find the subset C* whose …

2-approximating feedback vertex set in tournaments

D Lokshtanov, P Misra, J Mukherjee, F Panolan… - Proceedings of the …, 2020 - SIAM
A tournament is a directed graph T such that every pair of vertices is connected by an arc. A
feedback vertex set is a set S of vertices in T such that T–S is acyclic. We consider the …