,
Sukanya Pandey
,
Krisztina Szilágyi
Creative Commons Attribution 4.0 International license
Given a planar graph, a subset of its vertices called terminals, and k ∈ ℕ, the Face Cover Number problem asks whether the terminals lie on the boundaries of at most k faces of some embedding of the input graph. When a plane graph is given in the input, the problem is known to have a polynomial kernel [Valentin Garnero et al., 2017]. In this paper, we present the first polynomial kernel for Face Cover Number when the input is a planar graph (without a fixed embedding). Our approach overcomes the challenge of not having a predefined set of face boundaries by building a kernel bottom-up on an SPR-tree while preserving the essential properties of the face cover along the way.
@InProceedings{hamm_et_al:LIPIcs.STACS.2026.50,
author = {Hamm, Thekla and Pandey, Sukanya and Szil\'{a}gyi, Krisztina},
title = {{A Polynomial Kernel for Face Cover on Non-Embedded Planar Graphs}},
booktitle = {43rd International Symposium on Theoretical Aspects of Computer Science (STACS 2026)},
pages = {50:1--50:18},
series = {Leibniz International Proceedings in Informatics (LIPIcs)},
ISBN = {978-3-95977-412-3},
ISSN = {1868-8969},
year = {2026},
volume = {364},
editor = {Mahajan, Meena and Manea, Florin and McIver, Annabelle and Thắng, Nguy\~{ê}n Kim},
publisher = {Schloss Dagstuhl -- Leibniz-Zentrum f{\"u}r Informatik},
address = {Dagstuhl, Germany},
URL = {https://drops.dagstuhl.de/entities/document/10.4230/LIPIcs.STACS.2026.50},
URN = {urn:nbn:de:0030-drops-255392},
doi = {10.4230/LIPIcs.STACS.2026.50},
annote = {Keywords: Kernelization, Planar Graphs, SPQR-tree}
}