Abstract
Treedepth is an increasingly popular graph invariant. Many NP-hard combinatorial problems can be solved efficiently on graphs of bounded treedepth. Since the exact computation of treedepth is itself NP-hard, recent research has focused on the development of heuristics that compute good upper bounds on the treedepth.
In this paper, we introduce a novel MaxSAT-based approach for improving a heuristically obtained treedepth decomposition. At the core of our approach is an efficient MaxSAT encoding of a weighted generalization of treedepth arising naturally due to subtree contractions. The encoding is applied locally to the given treedepth decomposition to reduce its depth, in conjunction with the collapsing of subtrees. We show the local improvement method’s correctness and provide an extensive experimental evaluation with some encouraging results.
The authors acknowledge the support by the FWF (projects P32441 and W1255) and by the WWTF (project ICT19-065).
Access this chapter
Tax calculation will be finalised at checkout
Purchases are for personal use only
Similar content being viewed by others
References
Bannach, M., Berndt, S., Ehlers, T.: Jdrasil: a modular library for computing tree decompositions. In: Iliopoulos, C.S., Pissis, S.P., Puglisi, S.J., Raman, R. (eds.) 16th International Symposium on Experimental Algorithms, SEA 2017, London, UK, 21–23 June 2017, vol. 75, pp. 28:1–28:21. LIPIcs, Schloss Dagstuhl - Leibniz-Zentrum fuer Informatik (2017)
Berg, J., Järvisalo, M.: SAT-based approaches to treewidth computation: an evaluation. In: 26th IEEE International Conference on Tools with Artificial Intelligence, ICTAI 2014, Limassol, Cyprus, 10–12 November 2014, pp. 328–335. IEEE Computer Society (2014)
Dechter, R., Mateescu, R.: AND/OR search spaces for graphical models. Artif. Intell. 171(2–3), 73–106 (2007)
Fichte, J.K., Hecher, M., Lodha, N., Szeider, S.: An SMT approach to fractional hypertree width. In: Hooker, J. (ed.) CP 2018. LNCS, vol. 11008, pp. 109–127. Springer, Cham (2018). https://doi.org/10.1007/978-3-319-98334-9_8
Fichte, J.K., Lodha, N., Szeider, S.: SAT-based local improvement for finding tree decompositions of small width. In: Gaspers, S., Walsh, T. (eds.) SAT 2017. LNCS, vol. 10491, pp. 401–411. Springer, Cham (2017). https://doi.org/10.1007/978-3-319-66263-3_25
Fomin, F.V., Giannopoulou, A.C., Pilipczuk, M.: Computing tree-depth faster than 2\({}^{\text{ n }}\). Algorithmica 73(1), 202–216 (2015)
Freuder, E.C., Quinn, M.J.: Taking advantage of stable sets of variables in constraint satisfaction problems. In: IJCAI, vol. 85, pp. 1076–1078. Citeseer (1985)
GajarskĂ½, J., HlinenĂ½, P.: Faster deciding MSO properties of trees of fixed height, and some consequences. In: D’Souza, D., Kavitha, T., Radhakrishnan, J. (eds.) IARCS Annual Conference on Foundations of Software Technology and Theoretical Computer Science, FSTTCS 2012, Hyderabad, India, 15–17 December 2012, vol. 18, pp. 112–123. LIPIcs, Schloss Dagstuhl - Leibniz-Zentrum fuer Informatik (2012)
Ganian, R., Lodha, N., Ordyniak, S., Szeider, S.: SAT-encodings for treecut width and treedepth. In: Kobourov, S.G., Meyerhenke, H. (eds.) Proceedings of ALENEX 2019, the 21st Workshop on Algorithm Engineering and Experiments, pp. 117–129. SIAM (2019)
Gutin, G., Jones, M., Wahlström, M.: Structural parameterizations of the mixed Chinese postman problem. In: Bansal, N., Finocchi, I. (eds.) ESA 2015. LNCS, vol. 9294, pp. 668–679. Springer, Heidelberg (2015). https://doi.org/10.1007/978-3-662-48350-3_56
Hafsteinsson, H.: Parallel sparse Cholesky factorization. Cornell University, Technical report (1988)
Hagberg, A.A., Schult, D.A., Swart, P.J.: Exploring network structure, dynamics, and function using NetworkX. In: Proceedings of the 7th Python in Science Conference (SciPy 2008), Pasadena, CA, USA, pp. 11–15, August 2008
Heule, M., Szeider, S.: A SAT approach to clique-width. ACM Trans. Comput. Log. 16(3), 24 (2015). https://doi.org/10.1145/2736696
Ignatiev, A., Morgado, A., Marques-Silva, J.: PySAT: a Python toolkit for prototy** with SAT Oracles. In: Beyersdorff, O., Wintersteiger, C.M. (eds.) SAT 2018. LNCS, vol. 10929, pp. 428–437. Springer, Cham (2018). https://doi.org/10.1007/978-3-319-94144-8_26
Iwata, Y., Ogasawara, T., Ohsaka, N.: On the power of tree-depth for fully polynomial FPT algorithms. In: Niedermeier, R., Vallée, B. (eds.) 35th Symposium on Theoretical Aspects of Computer Science, STACS 2018, 28 February–3 March 2018, Caen, France, vol. 96, pp. 41:1–41:14. LIPIcs, Schloss Dagstuhl - Leibniz-Zentrum fuer Informatik (2018)
Iyer, A.V., Ratliff, H.D., Vijayan, G.: On a node ranking problem of trees and graphs. Technical reporrt, Georgia Inst of Tech Atlanta Production and Distribution Research Center (1986)
Jégou, P., Terrioux, C.: Hybrid backtracking bounded by tree-decomposition of constraint networks. Artif. Intell. 146(1), 43–75 (2003)
Jess, J.A.G., Kees, H.G.M.: A data structure for parallel L/U decomposition. IEEE Trans. Comput. 3, 231–239 (1982)
Kayaaslan, E., Uçar, B.: Reducing elimination tree height for parallel LU factorization of sparse unsymmetric matrices. In: 2014 21st International Conference on High Performance Computing (HiPC), pp. 1–10. IEEE (2014)
Kees, H.G.M.: The organization of circuit analysis on array architectures. Ph.D. thesis, Citeseer (1982)
Liu, J.W.: Reordering sparse matrices for parallel elimination. Parallel Comput. 11(1), 73–91 (1989)
Liu, J.W.: The role of elimination trees in sparse factorization. SIAM J. Mat. Anal. Appl. 11(1), 134–172 (1990)
Llewellyn, D.C., Tovey, C., Trick, M.: Local optimization on graphs. Discrete Appl. Math. 23(2), 157–178 (1989)
Lodha, N., Ordyniak, S., Szeider, S.: A SAT approach to branchwidth. In: Creignou, N., Le Berre, D. (eds.) SAT 2016. LNCS, vol. 9710, pp. 179–195. Springer, Cham (2016). https://doi.org/10.1007/978-3-319-40970-2_12
Lodha, N., Ordyniak, S., Szeider, S.: SAT-encodings for special treewidth and pathwidth. In: Gaspers, S., Walsh, T. (eds.) SAT 2017. LNCS, vol. 10491, pp. 429–445. Springer, Cham (2017). https://doi.org/10.1007/978-3-319-66263-3_27
Lodha, N., Ordyniak, S., Szeider, S.: A SAT approach to branchwidth. ACM Trans. Comput. Log. 20(3), 15:1–15:24 (2019)
Lusseau, D., Schneider, K., Boisseau, O.J., Haase, P., Slooten, E., Dawson, S.M.: The bottlenose dolphin community of doubtful sound features a large proportion of long-lasting associations. Behav. Ecol. Sociobiol. 54(4), 396–405 (2003)
Manne, F.: Reducing the height of an elimination tree through local recorderings. University of Bergen, Department of Informatics (1991)
Nesetril, J., de Mendez, P.O.: Tree-depth, subgraph coloring and homomorphism bounds. Eur. J. Comb. 27(6), 1022–1041 (2006)
Nešetřil, J., de Mendez, P.O.: Sparsity - Graphs, Structures, and Algorithms. Algorithms and Combinatorics, vol. 28. Springer, Heidelberg (2012). https://doi.org/10.1007/978-3-642-27875-4
Oelschlägel, T.: Treewidth from Treedepth. Ph.D. thesis, RWTH Aachen University (2014)
Peruvemba Ramaswamy, V., Szeider, S.: aditya95sriram/td-slim: public release, July 2020. Zenodo. https://doi.org/10.5281/zenodo.3946663
Peruvemba Ramaswamy, V., Szeider, S.: Turbocharging treewidth-bounded Bayesian network structure learning (2020). https://arxiv.org/abs/2006.13843
Pieck, J.: Formele definitie van een e-tree. Eindhoven University of Technology: Department of Mathematics: Memorandum 8006 (1980)
Pisinger, D., Ropke, S.: Large neighborhood search. In: Gendreau, M., Potvin, J.Y. (eds.) Handbook of Metaheuristics, pp. 399–419. Springer, Boston (2010). https://doi.org/10.1007/978-1-4419-1665-5_13
Pothen, A.: The complexity of optimal elimination trees. Technical report (1988)
Pothen, A., Simon, H.D., Wang, L., Barnard, S.T.: Towards a fast implementation of spectral nested dissection. In: Supercomputing 1992: Proceedings of the 1992 ACM/IEEE Conference on Supercomputing, pp. 42–51. IEEE (1992)
Reidl, F., Rossmanith, P., Villaamil, F.S., Sikdar, S.: A faster parameterized algorithm for treedepth. In: Esparza, J., Fraigniaud, P., Husfeldt, T., Koutsoupias, E. (eds.) ICALP 2014. LNCS, vol. 8572, pp. 931–942. Springer, Heidelberg (2014). https://doi.org/10.1007/978-3-662-43948-7_77
Samer, M., Veith, H.: Encoding treewidth into SAT. In: Kullmann, O. (ed.) SAT 2009. LNCS, vol. 5584, pp. 45–50. Springer, Heidelberg (2009). https://doi.org/10.1007/978-3-642-02777-2_6
Schidler, A., Szeider, S.: Computing optimal hypertree decompositions. In: Blelloch, G., Finocchi, I. (eds.) Proceedings of ALENEX 2020, the 22nd Workshop on Algorithm Engineering and Experiments, pp. 1–11. SIAM (2020)
Swat, S.: swacisko/pace-2020: first release of ExTREEm, June 2020. Zenodo. https://doi.org/10.5281/zenodo.3873126
Villaamil, F.S.: About treedepth and related notions. Ph.D. thesis, RWTH Aachen University (2017)
Author information
Authors and Affiliations
Corresponding author
Editor information
Editors and Affiliations
Rights and permissions
Copyright information
© 2020 Springer Nature Switzerland AG
About this paper
Cite this paper
Peruvemba Ramaswamy, V., Szeider, S. (2020). MaxSAT-Based Postprocessing for Treedepth. In: Simonis, H. (eds) Principles and Practice of Constraint Programming. CP 2020. Lecture Notes in Computer Science(), vol 12333. Springer, Cham. https://doi.org/10.1007/978-3-030-58475-7_28
Download citation
DOI: https://doi.org/10.1007/978-3-030-58475-7_28
Published:
Publisher Name: Springer, Cham
Print ISBN: 978-3-030-58474-0
Online ISBN: 978-3-030-58475-7
eBook Packages: Computer ScienceComputer Science (R0)