Abstract
We implement an online judge for context-free grammars. Our system contains a list of problems describing formal languages, and asking for grammars generating them. A submitted proposal grammar receives a verdict of acceptance or rejection depending on whether the judge determines that it is equivalent to the reference solution grammar provided by the problem setter. Since equivalence of context-free grammars is an undecidable problem, we consider a maximum length ℓ and only test equivalence of the generated languages up to words of length ℓ. This length restriction is very often sufficient for the well-meant submissions. Since this restricted problem is still NP-complete, we design and implement methods based on hashing, SAT, and automata that perform well in practice.
The authors were supported by an FPU grant (first author) and the FORMALISM project (TIN2007-66523) from the Spanish Ministry of Education and Science.
Access provided by Autonomous University of Puebla. Download to read the full chapter text
Chapter PDF
Similar content being viewed by others
References
Agarwal, A.: edX (2012), https://www.edx.org
Alexandrova, S., Balandin, A., Compeau, P., Kladov, A., Rayko, M., Sosa, E., Vyahhi, N., Dvorkin, M.: Rosalind (2012), http://www.rosalind.info
Axelsson, R., Heljanko, K., Lange, M.: Analyzing context-free grammars using an incremental SAT solver. In: Aceto, L., Damgård, I., Goldberg, L.A., Halldórsson, M.M., Ingólfsdóttir, A., Walukiewicz, I. (eds.) ICALP 2008, Part II. LNCS, vol. 5126, pp. 410–422. Springer, Heidelberg (2008)
Biere, A.: PicoSAT essentials. Journal on Satisfiability, Boolean Modeling and Computation 4(2-4), 75–97 (2008)
Eén, N., Sörensson, N.: An extensible SAT-solver. In: Giunchiglia, E., Tacchella, A. (eds.) SAT 2003. LNCS, vol. 2919, pp. 502–518. Springer, Heidelberg (2004)
Ganesh, V., Kieżun, A., Artzi, S., Guo, P.J., Hooimeijer, P., Ernst, M.: HAMPI: A string solver for testing, analysis and vulnerability detection. In: Gopalakrishnan, G., Qadeer, S. (eds.) CAV 2011. LNCS, vol. 6806, pp. 1–19. Springer, Heidelberg (2011)
García, C., Revilla, M.A.: UVa online judge (1997), http://uva.onlinejudge.org
Hooker, J.N.: Solving the incremental satisfiability problem. Journal of Logic Programming 15(1&2), 177–186 (1993)
Hopcroft, J.E., Motwani, R., Ullman, J.D.: Introduction to Automata Theory, Languages, and Computation, 3rd edn. Addison-Wesley (2006)
Khan, S.: Khan Academy (2006), https://www.khanacademy.org
Knuth, D.E.: The Art of Computer Programming, vol. III: Sorting and Searching. Addison-Wesley (1973)
Moskewicz, M.W., Madigan, C.F., Zhao, Y., Zhang, L., Malik, S.: Chaff: Engineering an efficient SAT solver. In: Annual ACM IEEE Design Automation Conference, pp. 530–535. ACM (2001)
Ng, A., Koller, D.: Coursera (2012), https://www.coursera.org
Petit, J., Giménez, O., Roura, S.: Jutge.org: an educational programming judge. In: ACM Special Interest Group on Computer Science Education, pp. 445–450 (2012)
Thrun, S., Stavens, D., Sokolsky, M.: Udacity (2012), https://www.udacity.com
Whittemore, J., Kim, J., Sakallah, K.A.: SATIRE: A new incremental satisfiability engine. In: Design Automation Conference, pp. 542–545 (2001)
Author information
Authors and Affiliations
Editor information
Editors and Affiliations
Rights and permissions
Copyright information
© 2014 Springer International Publishing Switzerland
About this paper
Cite this paper
Creus, C., Godoy, G. (2014). Automatic Evaluation of Context-Free Grammars (System Description). In: Dowek, G. (eds) Rewriting and Typed Lambda Calculi. RTA TLCA 2014 2014. Lecture Notes in Computer Science, vol 8560. Springer, Cham. https://doi.org/10.1007/978-3-319-08918-8_10
Download citation
DOI: https://doi.org/10.1007/978-3-319-08918-8_10
Publisher Name: Springer, Cham
Print ISBN: 978-3-319-08917-1
Online ISBN: 978-3-319-08918-8
eBook Packages: Computer ScienceComputer Science (R0)