Abstract
A number of different satisfaction and optimisation combinatorial problems have recently been approached with constraint programming over the domain of finite sets, for increased declarativity and efficiency. Such problems where one tries to find sets of values that satisfy some conditions, often present much symmetry on variables and values. In particular, the social golfers problem encompasses many possible symmetries. Allowing symmetric solutions increases search space unnecessarily, thus multiplying solution time. Therefore, ordering constraints have been proposed and incorporated in set solvers. However, such constraints are imposed statically in the global problem model and are unable to detect symmetries that still occur in sub-problems after a partial labelling. In this paper we discuss how to overcome this and present an approach that sequentially labels variables avoiding such symmetries by dynamically disallowing the assignment of other values from the same equivalence class in the golfers problem. Experimental results show that this approach outperforms previous ones, recently achieved by the constraint programming community, namely over sets. Unfortunately, the current method is incomplete and may loose solutions. Nevertheless, results are correct and show that similar techniques can be used efficiently to obtain faster solutions.
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References
Anderson, I., Honkala, I.: A Short Course in Combinatorial Designs (1997), http://www.utu.fi/~honkala/cover.html
Azevedo, F.: Constraint Solving over Multi-valued Logics - Application to Digital Circuits. In: Frontiers of Artificial Intelligence and Applications, vol. 91, IOS Press, Amsterdam (2003)
Azevedo, F.: Cardinal: A Finite Sets Constraint Solver. Constraints journal KAP (to appear, 2007)
Azevedo, F., Barahona, P.: Modelling Digital Circuits Problems with Set Constraints. In: Palamidessi, C., Moniz Pereira, L., Lloyd, J.W., Dahl, V., Furbach, U., Kerber, M., Lau, K.-K., Sagiv, Y., Stuckey, P.J. (eds.) CL 2000. LNCS (LNAI), vol. 1861, pp. 414–428. Springer, Heidelberg (2000)
Barnier, N., Brisset, P.: Solving the Kirkman’s Schoolgirl Problem in a Few Seconds. In: Van Hentenryck, P. (ed.) CP 2002. LNCS, vol. 2470, pp. 477–491. Springer, Heidelberg (2002)
Beldiceanu, N.: An Example of Introduction of Global Constraints in CHIP: Application to Block Theory Problems. Technical Report TR-LP-49. ECRC, Munich, Germany (1990)
Choueiry, Noubir: On the Computation of Local Interchangeability in Discrete Constraint Satisfaction Problems. In: Proc. AAAI 1998 (1998)
Colbourn, C.J., Dinitz, J.H. (eds.): Steiner Triple Systems. CRC Handbook of Combinatorial Designs, vol. 70, pp. 14–15, CRC Press, Boca Raton, FL (1996)
Fahle, T., Shamberger, S., Sellmann, M.: Symmetry Breaking. In: Walsh, T. (ed.) CP 2001. LNCS, vol. 2239, pp. 93–107. Springer, Heidelberg (2001)
Focacci, F., Milano, M.: Global Cut Framework for Removing Symmetries. In: Walsh, T. (ed.) CP 2001. LNCS, vol. 2239, pp. 75–92. Springer, Heidelberg (2001)
Gent, I.P., Harvey, W., Kelsey, T.: Groups and Constraints: Symmetry Breaking During Search. In: Van Hentenryck, P. (ed.) CP 2002. LNCS, vol. 2470, pp. 415–430. Springer, Heidelberg (2002)
Gent, I.P., Smith, B.M.: Symmetry Breaking During Search in Constraint Programming. In: Proc. ECAI 2000 (2000)
Gervet, C.: Interval Propagation to Reason about Sets: Definition and Implementation of a Practical Language. In: Freuder, E.C. (ed.): Constraints journal, vol. 1(3), pp. 191–244, Kluwer Academic Publishers (1997)
Harvey, W.: Symmetry Breaking and the Social Golfer Problem. In: Walsh, T. (ed.) CP 2001. LNCS, vol. 2239, Springer, Heidelberg (2001)
Hawkins, P., Lagoon, V., Stuckey, P.J.: Set Bounds and (Split) Set Domain Propagation Using ROBDDs. In: Webb, G.I., Yu, X. (eds.) AI 2004. LNCS (LNAI), vol. 3339, pp. 706–717. Springer, Heidelberg (2004)
Van Hentenryck, P.: A Logic Language for Combinatorial Optimization. In: Annals of Operations Research (1989)
Kirkman, T.P.: On a problem in combinatorics. Cambridge and Dublin Math. Journal, 191–204 (1847)
Kiziltan, Z.: Symmetry Breaking Ordering Constraints. PhD thesis, Uppsala University (2004)
Lagoon, V., Stuckey, P.J.: Set Domain Propagation Using ROBDDs. In: Wallace, M. (ed.) CP 2004. LNCS, vol. 3258, pp. 347–361. Springer, Heidelberg (2004)
Lindner, C.C., Rosa, A.: Topics on Steiner Systems. Annals of Discrete Mathematics, vol. 7. North Holland, Amsterdam (1980)
Lueneburg, H.: Tools and Fundamental Constructions of Combinatorial Mathematics, Wissenschaftverlag (1989)
Meseguer, P., Torras, C.: Exploiting Symmetries Within Constraint Satisfaction Search. Art.Intell. 129, 133–163 (1999)
Puget, J.-F.: PECOS: A High Level Constraint programming Language. In: Proc. Spicis 92, Singapore (1992)
Puget, J.-F.: Symmetry Breaking Revisited. In: Van Hentenryck, P. (ed.) CP 2002. LNCS, vol. 2470, pp. 446–461. Springer, Heidelberg (2002)
Puget, J.-F.: Symmetry Breaking Using Stabilizers. In: Rossi, F. (ed.) CP 2003. LNCS, vol. 2833, Springer, Heidelberg (2003)
Roney-Dougal, C.M., Gent, I.P., Kelsey, T., Linton, S.A.: Tractable symmetry breaking using restricted search trees. In: Proceedings of ECAI 2004 (2004)
Sellmann, M., Harvey, W.: Heuristic Constraint Propagation. In: Proceedings of CPAIOR 2002 workshop, pp. 191–204 (2002)
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Azevedo, F. (2007). An Attempt to Dynamically Break Symmetries in the Social Golfers Problem. In: Azevedo, F., Barahona, P., Fages, F., Rossi, F. (eds) Recent Advances in Constraints. CSCLP 2006. Lecture Notes in Computer Science(), vol 4651. Springer, Berlin, Heidelberg. https://doi.org/10.1007/978-3-540-73817-6_2
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DOI: https://doi.org/10.1007/978-3-540-73817-6_2
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