English

Unified almost linear kernels for generalized covering and packing problems on nowhere dense classes

Data Structures and Algorithms 2022-07-15 v1 Combinatorics

Abstract

Let F\mathcal{F} be a family of graphs, and let p,rp,r be nonnegative integers. The \textsc{(p,r,F)(p,r,\mathcal{F})-Covering} problem asks whether for a graph GG and an integer kk, there exists a set DD of at most kk vertices in GG such that GpNGr[D]G^p\setminus N_G^r[D] has no induced subgraph isomorphic to a graph in F\mathcal{F}, where GpG^p is the pp-th power of GG. The \textsc{(p,r,F)(p,r,\mathcal{F})-Packing} problem asks whether for a graph GG and an integer kk, GpG^p has kk induced subgraphs H1,,HkH_1,\ldots,H_k such that each HiH_i is isomorphic to a graph in F\mathcal{F}, and for distinct i,j{1,,k}i,j\in \{1, \ldots, k\}, the distance between V(Hi)V(H_i) and V(Hj)V(H_j) in GG is larger than rr. We show that for every fixed nonnegative integers p,rp,r and every fixed nonempty finite family F\mathcal{F} of connected graphs, the \textsc{(p,r,F)(p,r,\mathcal{F})-Covering} problem with p2r+1p\leq2r+1 and the \textsc{(p,r,F)(p,r,\mathcal{F})-Packing} problem with p2r/2+1p\leq2\lfloor r/2\rfloor+1 admit almost linear kernels on every nowhere dense class of graphs, and admit linear kernels on every class of graphs with bounded expansion, parameterized by the solution size kk. We obtain the same kernels for their annotated variants. As corollaries, we prove that \textsc{Distance-rr Vertex Cover}, \textsc{Distance-rr Matching}, \textsc{F\mathcal{F}-Free Vertex Deletion}, and \textsc{Induced-F\mathcal{F}-Packing} for any fixed finite family F\mathcal{F} of connected graphs admit almost linear kernels on every nowhere dense class of graphs and linear kernels on every class of graphs with bounded expansion. Our results extend the results for \textsc{Distance-rr Dominating Set} by Drange et al. (STACS 2016) and Eickmeyer et al. (ICALP 2017), and the result for \textsc{Distance-rr Independent Set} by Pilipczuk and Siebertz (EJC 2021).

Keywords

Cite

@article{arxiv.2207.06660,
  title  = {Unified almost linear kernels for generalized covering and packing problems on nowhere dense classes},
  author = {Jungho Ahn and Jinha Kim and O-joung Kwon},
  journal= {arXiv preprint arXiv:2207.06660},
  year   = {2022}
}

Comments

38 pages

R2 v1 2026-06-25T00:54:12.718Z