Abstract
In this paper, a new approach is presented to qualify or not, a solution found by a heuristic for a potential optimal solution. Our approach is based on the following observation: for a minimization problem, the number of admissible solutions decreases with the value of the objective function. Concerning the Graph Coloring Problem (GCP), we confirm this observation and present a new way in which to prove optimality. This proof is based on the counting of the number of different k-colorings and the number of independent sets of a given graph G.
Finding the exact solution for counting problems is difficult (#P-complete). However, we show that in using only randomized heuristics, it is possible to define an estimation of the upper bound of the number of k-colorings. This estimate has been calibrated on a broad benchmark of graph instances for which the exact number of optimal k-colorings is known.
Our approach, called optimality clue, constructs a sample of k-colorings from a given graph by running one randomized heuristic a number of times on the same graph instance. We use the evolutionary algorithm HEAD [26], which is one of the most efficient heuristics for GCP.
Optimality clue matches the standard definition of optimality on a wide number of instances for DIMACS and RBCII benchmarks where the optimality is known.
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Notes
- 1.
Notice that it is still NP-hard to approximate \(\chi (G)\) within \(n^{1-\epsilon }\) for any \(\epsilon > 0\) [35].
- 2.
A perfect graph is a graph for which the chromatic number of every induced subgraph is the same as the size of the largest clique of that subgraph. 1-perfect graphs are more general than perfect graphs.Polynomial-time exact algorithms with the aim of finding \(\chi (G)\) for perfect graphs [13] exist, but are in reality slow in performance. Line graphs, chordal graphs, interval graphs or cographs are subclasses of perfect graphs.
- 3.
An independent set is a subset of vertices of G, so every two distinct vertices in the independent set are not adjacent.
- 4.
Open-source code available at: github.com/graphcoloring/HEAD.
- 5.
A maximal clique is a clique that cannot be extended by including an additional adjacent vertex. A maximum clique is a clique that has the largest size in a given graph; a maximum clique is therefore always maximal, but the converse is not so. Analogue definition for IS.
- 6.
Code available at: https://users.aalto.fi/~pat/cliquer.html. To count all IS of a graph, you just execute: ./cl \({<}\)complement graph\({>}\) -a -m 1 -M \({<}k{>}\).
- 7.
All k-colorings in the sample are uniformly drawn at random in \(\varOmega (G,k)\).
- 8.
The fitness landscape itself depends on the neighborhood used for both the tabu search and the crossover.
- 9.
This problem is linked to the birthday problem that shows that in a room of just 23 people there’s a 50-50 chance that two people have the same birthday. In our case, the number of days in a year is \(\mathcal {N}\) and the number of people is the size t of the sample.
- 10.
Code available at: lamsade.dauphine.fr/coloring/doku.php.
- 11.
Instances available in the same address.
- 12.
For <DSJC500.5> the computation time is not reported because it takes several weeks and no accurate time has been recorded.
- 13.
In this context, we propose on our website a challenge to find a counterexample (false positive graph).
References
Baillargeon, S., Rivest, L.P.: Rcapture: loglinear models for capture-recapture in R. J. Stat. Softw. Art. 19(5), 1–31 (2007)
BollobĂ¡s, B.: Random Graphs. Cambridge Studies in Advanced Mathematics, 2 edn. Cambridge University Press (2001). https://doi.org/10.1017/CBO9780511814068
Brélaz, D.: New methods to color the vertices of a graph. Commun. ACM 22(4), 251–256 (1979)
Bron, C., Kerbosch, J.: Algorithm 457: finding all cliques of an undirected graph. Commun. ACM 16(9), 575–577 (1973). https://doi.org/10.1145/362342.362367
Carraghan, R., Pardalos, P.M.: An exact algorithm for the maximum clique problem. Oper. Res. Lett. 9(6), 375–382 (1990). https://doi.org/10.1016/0167-6377(90)90057-C
Ermon, S., Gomes, C.P., Selman, B.: Uniform solution sampling using a constraint solver as an oracle. In: de Freitas, N., Murphy, K.P. (eds.) Proceedings of the Twenty-Eighth Conference on Uncertainty in Artificial Intelligence, Catalina Island, CA, USA, 14–18 August 2012, pp. 255–264. AUAI Press (2012)
Favier, A., de Givry, S., Jégou, P.: Solution counting for CSP and SAT with large tree-width. Control Syst. Comput. 2, 4–13 (2011)
Frieze, A., Vigoda, E.: A survey on the use of Markov chains to randomly sample colourings. Oxford University Press, Oxford (2007). Chap. 4. https://doi.org/10.1093/acprof:oso/9780198571278.003.0004
Furini, F., Gabrel, V., Ternier, I.: An improved DSATUR-based branch-and-bound algorithm for the vertex coloring problem. Networks 69(1), 124–141 (2017). https://doi.org/10.1002/net.21716
Galinier, P., Hao, J.K.: Hybrid evolutionary algorithms for graph coloring. J. Comb. Optim. 3(4), 379–397 (1999). https://doi.org/10.1023/A:1009823419804
Gomes, C.P., Hoffmann, J., Sabharwal, A., Selman, B.: From sampling to model counting. In: IJCA Proceedings IJCAI 2007, pp. 2293–2299. IJCAI (2007)
Gomes, C.P., Sabharwal, A., Selman, B.: Model counting. In: Biere, A., Heule, M., van Maaren, H., Walsh, T. (eds.) Handbook of Satisfiability, Frontiers in Artificial Intelligence and Applications, vol. 185, pp. 633–654. IOS Press (2009). https://doi.org/10.3233/978-1-58603-929-5-633
Grötschel, M., LovĂ¡sz, L., Schrijver, A.: Polynomial algorithms for perfect graphs. In: Berge, C., ChvĂ¡tal, V. (eds.) Topics on Perfect Graphs, North-Holland Mathematics Studies, vol. 88, pp. 325–356. North-Holland (1984). https://doi.org/10.1016/S0304-0208(08)72943-8
Gusfield, D.: Partition-distance: a problem and class of perfect graphs arising in clustering. Inform. Process. Lett. 82(3), 159–164 (2002)
Held, S., Cook, W., Sewell, E.: Maximum-weight stable sets and safe lower bounds for graph coloring. Math. Program. Comput. 4(4), 363–381 (2012). https://doi.org/10.1007/s12532-012-0042-3
Jerrum, M.: A very simple algorithm for estimating the number of k-colorings of a low-degree graph. Random Struct. Algorithms 7(2), 157–165 (1995). https://doi.org/10.1002/rsa.3240070205
Jerrum, M.: Counting constraint satisfaction problems. In: Krokhin, A., Zivny, S. (eds.) The Constraint Satisfaction Problem: Complexity and Approximability, Dagstuhl Follow-Ups, vol. 7, pp. 205–231. Schloss Dagstuhl-Leibniz-Zentrum fuer Informatik, Dagstuhl, Germany (2017)
Johnson, D.S., Trick, M. (eds.): Cliques, Coloring, and Satisfiability: Second DIMACS Implementation Challenge, 1993, DIMACS Series in Discrete Mathematics and Theoretical Computer Science, vol. 26. American Mathematical Society, Providence (1996)
Karp, R.: Reducibility among combinatorial problems. In: Miller, R.E., Thatcher, J.W. (eds.) Complexity of Computer Computations, pp. 85–103. Plenum Press, New York (1972)
Krebs, C.J.: Ecology, 6th edn. Pearson, London (2009)
Li, C., Fang, Z., Xu, K.: Combining MaxSAT reasoning and incremental upper bound for the maximum clique problem. In: 2013 IEEE 25th International Conference on Tools with Artificial Intelligence, pp. 939–946, November 2013. https://doi.org/10.1109/ICTAI.2013.143
Malaguti, E., Toth, P.: A survey on vertex coloring problems. Int. Trans. Oper. Res. 17, 1–34 (2009)
Marmion, M.É., Jourdan, L., Dhaenens, C.: Fitness landscape analysis and metaheuristics efficiency. J. Math. Model. Algorithms Oper. Res. 12(1), 3–26 (2013). https://doi.org/10.1007/s10852-012-9177-5
Merz, P.: Memetic algorithms for combinatorial optimization problems: fitness landscapes and effective search strategies. Ph.D. thesis, Department of Electrical Engineering and Computer Science, University of Siegen, Germany (2000)
Miracle, S., Randall, D.: Algorithms to approximately count and sample conforming colorings of graphs. Discret. Appl. Math. 210(Suppl. C), 133–149 (2016). lAGOS 2013: Seventh Latin-American Algorithms, Graphs, and Optimization Symposium, Playa del Carmen, México – 2013
Moalic, L., Gondran, A.: Variations on memetic algorithms for graph. J. Heuristics 24(1), 1–24 (2018). https://doi.org/10.1007/s10732-017-9354-9
Orlin, J., Bonuccelli, M., Bovet, D.: An \(O(n^2)\) algorithm for coloring proper circular arc graphs. SIAM J. Algebraic Discret. Methods 2(2), 88–93 (1981). https://doi.org/10.1137/0602012
Ă–stergĂ¥rd, P.R.: A fast algorithm for the maximum clique problem. Discret. Appl. Math. 120(1), 197–207 (2002). https://doi.org/10.1016/S0166-218X(01)00290-6. Special Issue devoted to the 6th Twente Workshop on Graphs and Combinatorial Optimization
Pedersen, A.S.P., Vestergaard, P.D.: Bounds on the number of vertex independent sets in a graph. Taiwan. J. Math. 10(6), 1575–1587 (2006)
Samotij, W.: Counting independent sets in graphs. Eur. J. Comb. 48, 5–18 (2015). https://doi.org/10.1016/j.ejc.2015.02.005
Shih, W.K., Hsu, W.L.: An \(O(n^{1.5})\) algorithm to color proper circular arcs. Discret. Appl. Math. 25(3), 321–323 (1989). https://doi.org/10.1016/0166-218X(89)90011-5
Titiloye, O., Crispin, A.: Parameter tuning patterns for random graph coloring with quantum annealing. PLoS ONE 7(11), e50060 (2012). https://doi.org/10.1371/journal.pone.0050060
Valiant, L.G.: The complexity of enumeration and reliability problems. SIAM J. Comput. 8(3), 410–421 (1979). https://doi.org/10.1137/0208032
Wei, W., Selman, B.: A new approach to model counting. In: Bacchus, F., Walsh, T. (eds.) SAT 2005. LNCS, vol. 3569, pp. 324–339. Springer, Heidelberg (2005). https://doi.org/10.1007/11499107_24
Zuckerman, D.: Linear degree extractors and the inapproximability of max clique and chromatic number. Theory Comput. 3(6), 103–128 (2007). https://doi.org/10.4086/toc.2007.v003a006. http://www.theoryofcomputing.org/articles/v003a006
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Gondran, A., Moalic, L. (2019). Optimality Clue for Graph Coloring Problem. In: Rousseau, LM., Stergiou, K. (eds) Integration of Constraint Programming, Artificial Intelligence, and Operations Research. CPAIOR 2019. Lecture Notes in Computer Science(), vol 11494. Springer, Cham. https://doi.org/10.1007/978-3-030-19212-9_22
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