Abstract
Let d-claw (or d-star) stand for \(K_{1,d}\), the complete bipartite graph with 1 and \(d\ge 1\) vertices on each part. The d-claw vertex deletion problem, \(d\)-claw-vd, asks for a given graph G and an integer k if one can delete at most k vertices from G such that the resulting graph has no d-claw as an induced subgraph. Thus, \(1\)-claw-vd and \(2\)-claw-vd are just the famous vertex cover problem and the cluster vertex deletion problem, respectively. In this paper, we strengthen a hardness result recently proved in Jena and Subramani (in: Du, Du, Wu, and Zhu (eds) Theory and applications of models of computation - 17th annual conference, TAMC 2022, Tianjin, China, September 16–18, 2022, Proceedings, 2022), by showing that cluster vertex deletion remains \(\textsf{NP}\)-complete even when restricted to planar bipartite graphs of maximum degree 3 and arbitrary large girth. Moreover, for every \(d\ge 3\), we show that \(d\)-claw-vd is \(\textsf{NP}\)-complete even when restricted to planar bipartite graphs of maximum degree d. These hardness results are optimal with respect to degree constraint. By extending the hardness result in Bonomo-Braberman et al (in: Computing and combinatorics - 26th international conference, COCOON 2020, Proceedings, Lecture Notes in Computer Science, vol 12273, Springer, 2020, pp 14–26, 2020), we show that, for every \(d\ge 3\), \(d\)-claw-vd is \(\textsf{NP}\)-complete even when restricted to split graphs without \((d+1)\)-claws, and split graphs of diameter 2. On the positive side, we prove that \(d\)-claw-vd is polynomially solvable on what we call d-block graphs, a class properly contains all block graphs. This result extends the polynomial-time algorithm in Cao et al (Theor Comput Sci, 2018) for \(2\)-claw-vd on block graphs to \(d\)-claw-vd for all \(d\ge 2\) and improves the polynomial-time algorithm proposed by Bonomo-Brabeman et al. for (unweighted) \(3\)-claw-vd on block graphs to 3-block graphs.
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Notes
The \(O^*\) notation hides polynomial factors.
References
Bonomo-Braberman, F., Nascimento, J.R., Oliveira, F.S., Souza, U.S., Szwarcfiter, J.L.: Linear-time algorithms for eliminating claws in graphs. In: Computing and Combinatorics - 26th International Conference, COCOON: Proceedings, Lecture Notes in Computer Science, vol. 12273. Springer 2020, 14–26 (2020)
Bonomo-Braberman, F., Nascimento, J.R., Oliveira, F.S., Souza, U.S., Szwarcfiter, J.L.: Linear-time algorithms for eliminating claws in graphs. Int. Trans. Op.er Res. 0, 1–20 (2021)
Boral, A., Cygan, M., Kociumaka, T., Pilipczuk, M.: A fast branching algorithm for cluster vertex deletion. Theory Comput. Syst. 58(2), 357–376 (2016)
Cao, Y., Ke, Y., Otachi, Y., You, J.: Vertex deletion problems on chordal graphs. In: 37th IARCS Annual Conference on Foundations of Software Technology and Theoretical Computer Science, FSTTCS 2017, LIPIcs, vol. 93, pp. 22:1–22:14 (2017)
Cao, Y., Ke, Y., Otachi, Y., You, J.: Vertex deletion problems on chordal graphs. Theor. Comput. Sci. 745, 75–86 (2018)
Chang, M.-S., Chen, L.-H., Hung, L.-J., Rossmanith, P., Ping-Chen, S.: Fixed-parameter algorithms for vertex cover p\({}_{\text{3 }}\). Discrete Optim. 19, 12–22 (2016)
Chen, J., Kanj, I.A., Xia, G.: Improved upper bounds for vertex cover. Theor. Comput. Sci. 411(40–42), 3736–3756 (2010)
Crespelle, C., Drange, P.G., Fomin, F.V., Golovach, P.A.: A survey of parameterized algorithms and the complexity of edge modification. arXiv:2001.06867 (2020)
Fiorini, S., Joret, G., Schaudt, O.: Improved approximation algorithms for hitting 3-vertex paths. Math. Program. 182(1–2), 355–367 (2020)
Grötschel, M., Lovász, L., Schrijver, A.: Geometric Algorithms and Combinatorial Optimization. Springer (1988)
Guruswami, V., Lee, E.: Inapproximability of h-transversal/packing. SIAM J. Discrete Math. 31(3), 1552–1571 (2017)
Horton, J.D., Kilakos, K.: Minimum edge dominating sets. SIAM J. Discrete Math. 6(3), 375–387 (1993)
Hsieh, S.-Y., Le, V.B., Peng, S.L.: On the d-claw vertex deletion problem. In: Computing and Combinatorics - 27th International Conference, COCOON: Tainan, Taiwan, October 24–26, 2021, Proceedings, Lecture Notes in Computer Science, vol. 13025. Springer 2021, pp. 591–603 (2021)
Jena, S.K., Subramani, K.: Analyzing the 3-path vertex cover problem in planar bipartite graphs. In: Theory and Applications of Models of Computation - 17th Annual Conference, TAMC 2022, Tianjin, China, September 16–18, 2022, Proceedings (Du, D.-Z., Du, D., Wu, C., Xu, D. eds.), Lecture Notes in Computer Science, vol. 13571, Springer, pp. 103–115 (2022)
Khot, S., Regev, O.: Vertex cover might be hard to approximate to within 2-epsilon. J. Comput. Syst. Sci. 74(3), 335–349 (2008)
Kumar, M., Mishra, S., Devi, N.S., Saurabh, S.: Approximation algorithms for node deletion problems on bipartite graphs with finite forbidden subgraph characterization. Theor. Comput. Sci. 526, 90–96 (2014)
Le, H.-O., Le, V.B.: Complexity of the cluster vertex deletion problem on H-free graphs. In: 47th International Symposium on Mathematical Foundations of Computer Science, MFCS 2022, August 22–26, 2022, Vienna, Austria (Szeider, S., Ganian, R., Silva, A., eds.), LIPIcs, vol. 241, Schloss Dagstuhl - Leibniz-Zentrum für Informatik, pp. 68:1–68:10 (2022)
Lewis, J.M., Yannakakis, M.: The node-deletion problem for hereditary properties is NP-complete. J. Comput. Syst. Sci. 20(2), 219–230 (1980)
Lokshtanov, D., Marx, D., Saurabh, S.: Lower bounds based on the exponential time hypothesis. Bull. EATCS 105, 41–72 (2011)
Lund, C., Yannakakis, M.: The approximation of maximum subgraph problems. In: Automata, Languages and Programming, 20nd International Colloquium, ICALP93, Lecture Notes in Computer Science, vol. 700, Springer, pp. 40–51 (1993)
Moore, C., Robson, J.M.: Hard tiling problems with simple tiles. Discrete Comput. Geom. 26(4), 573–590 (2001)
Mulzer, W., Rote, G.: Minimum-weight triangulation is np-hard. J. ACM 55(2), 11:1–11:29 (2008)
Murphy, O.J.: Computing independent sets in graphs with large girth. Discrete Appl. Math. 35(2), 167–170 (1992)
Tsur, D.: Parameterized algorithm for 3-path vertex cover. Theor. Comput. Sci. 783, 1–8 (2019)
Tsur, D.: Faster parameterized algorithm for cluster vertex deletion. Theor. Comput. Syst. 65(2), 323–343 (2021)
Yannakakis, M.: Node-deletion problems on bipartite graphs. SIAM J. Comput. 10(2), 310–327 (1981)
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We thank Ling-Ju Hung (NTUB, Taoyuan, Taiwan) for pointing the paper [14] to us.
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A preliminary version [13] of this article has appeared in Proceedings of the 26th International Computing and Combinatorics Conference (COCOON 2021), Lecture Notes in Computer Science 13025, pp. 591–603.
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Hsieh, SY., Le, HO., Le, V.B. et al. On the d-Claw Vertex Deletion Problem. Algorithmica 86, 505–525 (2024). https://doi.org/10.1007/s00453-023-01144-w
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DOI: https://doi.org/10.1007/s00453-023-01144-w