Abstract
Given a vertex-weighted connected graph \(G = (V, E)\), the maximum weight internal spanning tree (MwIST for short) problem asks for a spanning tree T of G such that the total weight of internal vertices in T is maximized. The unweighted variant, denoted as MIST, is NP-hard and APX-hard, and the currently best approximation algorithm has a proven performance ratio of 13 / 17. The currently best approximation algorithm for MwIST only has a performance ratio of \(1/3 - \epsilon \), for any \(\epsilon > 0\). In this paper, we present a simple algorithm based on a novel relationship between MwIST and maximum weight matching, and show that it achieves a significantly better approximation ratio of 1/2. When restricted to claw-free graphs, a special case previously studied, we design a 7/12-approximation algorithm.
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Binkele-Raible, D., Fernau, H., Gaspers, S., Liedloff, M.: Exact and parameterized algorithms for max internal spanning tree. Algorithmica 65, 95–128 (2013)
Chen, Z.-Z., Harada, Y., Guo, F., Wang, L.: An approximation algorithm for maximum internal spanning tree. J. Comb. Optim. 35, 955–979 (2018)
Coben, N., Fomin, F.V., Gutin, G., Kim, E.J., Saurabh, S., Yeo, A.: Algorithm for finding \(k\)-vertex out-trees and its application to \(k\)-internal out-branching problem. J. Comput. Syst. Sci. 76, 650–662 (2010)
Fomin, F.V., Gaspers, S., Saurabh, S., Thomasse, S.: A linear vertex kernel for maximum internal spanning tree. J. Comput. Syst. Sci. 79, 1–6 (2013)
Fomin, F.V., Lokshtanov, D., Grandoni, F., Saurabh, S.: Sharp separation and applications to exact and parameterized algorithms. Algorithmica 63, 692–706 (2012)
Garey, M.R., Johnson, D.S.: Computers and Intractability: A Guide to the Theory of NP-Completeness. W. H. Freeman and Company, San Francisco (1979)
Knauer, M., Spoerhase, J.: Better approximation algorithms for the maximum internal spanning tree problem. In: Proceedings of WADS 2009, LNCS 5664, pp. 489–470 (2009)
Li, W., Chen, J., Wang, J.: Deeper local search for better approximation on maximum internal spanning tree. In: Proceedings of ESA 2014, LNCS 8737, pp. 642–653 (2014)
Li, W., Wang, J., Chen, J., Cao, Y.: A \(2k\)-vertex kernel for maximum internal spanning tree. In: Proceedings of WADS 2015, LNCS 9214, pp. 495–505 (2015)
Li, X., Jiang, H., Feng, H.: Polynomial time for finding a spanning tree with maximum number of internal vertices on interval graphs. In: Proceedings of FAW 2016, LNCS 9711, pp. 92–101 (2016)
Li, X., Zhu, D.: A \(4/3\)-approximation algorithm for the maximum internal spanning tree problem. CoRR, arXiv:1409.3700 (2014)
Li, X., Zhu, D.: Approximating the maximum internal spanning tree problem via a maximum path-cycle cover. In: Proceedings of ISAAC 2014, LNCS 8889, pp. 467–478 (2014)
Prieto, E.: Systematic kernelization in FPT algorithm design. In: Ph.D. Thesis, The University of Newcastle, Australia (2005)
Prieto, E., Sloper, C.: Either/or: using vertex cover structure in designing FPT-algorithms—the case of \(k\)-internal spanning tree. In: Proceedings of WADS 2003, LNCS 2748, pp. 474–483 (2003)
Prieto, E., Sloper, C.: Reducing to independent set structure—the case of \(k\)-internal spanning tree. Nord. J. Comput. 12, 308–318 (2005)
Salamon, G.: Approximating the maximum internal spanning tree problem. Theor. Comput. Sci. 410, 5273–5284 (2009)
Salamon, G.: Degree-based spanning tree optimization. In: Ph.D. Thesis, Budapest University of Technology and Economics, Hungary (2009)
Salamon, G., Wiener, G.: On finding spanning trees with few leaves. Inf. Process. Lett. 105, 164–169 (2008)
Acknowledgements
The authors are grateful to the reviewers for their insightful comments and for their suggested changes that improve the presentation greatly. ZZC was supported in part by the Grant-in-Aid for Scientific Research of the Ministry of Education, Culture, Sports, Science and Technology of Japan, under Grant No. 24500023. GL was supported by the NSERC Canada and the NSFC Grant No. 61672323; most of his work was done while visiting ZZC at the Tokyo Denki University at Hatoyama. LW is fully supported by a Grant from the Research Grants Council of the Hong Kong Special Administrative Region, China, CityU 11256116. YC was supported in part by the NSERC Canada, the NSFC Grants Nos. 11771114 and 11571252, and the China Scholarship Council Grant No. 201508330054.
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An extended abstract appears in the Proceedings of COCOON 2017. LNCS 10392, pp. 124–136.
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Chen, ZZ., Lin, G., Wang, L. et al. Approximation Algorithms for the Maximum Weight Internal Spanning Tree Problem. Algorithmica 81, 4167–4199 (2019). https://doi.org/10.1007/s00453-018-00533-w
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DOI: https://doi.org/10.1007/s00453-018-00533-w