human: Given a node-centered hypergraph: <hypergraph>, where nodes represent papers and hyperedges represent sets of papers co-cited by a source paper.

Details of the hypergraph:
Center node: "the qbf gallery"
  Abstract: Over the last few years, much progress has been made in the theory and practice of solving quantified Boolean formulas (QBF). Novel solvers have been presented that either successfully enhance established techniques or implement novel solving paradigms. Powerful preprocessors have been realized that tune the encoding of a formula to make it easier to solve. Frameworks for certification and solution extraction emerged that allow for a detailed interpretation of a QBF solver's results, and new types of QBF encodings were presented for various application problems.To capture these developments the QBF Gallery was established in 2013. The QBF Gallery aims at providing a forum to assess QBF tools and to collect new, expressive benchmarks that allow for documenting the status quo and that indicate promising research directions. These benchmarks became the basis for the experiments conducted in the context of the QBF Gallery 2013 and follow-up evaluations. In this paper, we report on the setup of the QBF Gallery. To this end, we conducted numerous experiments which allowed us not only to assess the quality of the tools, but also the quality of the benchmarks.

Connected through hyperedge HE-1 (induced by source paper "qratpre effective qbf preprocessing via strong redundancy properties"):
  with members:
    - "expansion based qbf solving without recursion"
    - "evaluating qbf solvers quantifier alternations matter"
    - "on expansion and resolution in cegar based qbf solving"
    - "textsf qrat generalizing qrat by a more powerful qbf redundancy property"
    - "depqbf 6 0 a search based qbf solver beyond traditional qcdcl"
    - "clause term resolution and learning in the evaluation of quantified boolean formulas"

Connected through hyperedge HE-2 (induced by source paper "evaluating qbf solvers quantifier alternations matter"):
  with members:
    - "on expansion and resolution in cegar based qbf solving"
    - "size cost and capacity a semantic technique for hard random qbfs"
    - "depqbf 6 0 a search based qbf solver beyond traditional qcdcl"
    - "proof complexity modulo the polynomial hierarchy understanding alternation as a source of hardness"
    - "meditations on quantified constraint satisfaction"
    - "clause term resolution and learning in the evaluation of quantified boolean formulas"

Connected through hyperedge HE-3 (induced by source paper "depqbf 6 0 a search based qbf solver beyond traditional qcdcl"):
  with members:
    - "evaluating qbf solvers quantifier alternations matter"
    - "q resolution with generalized axioms"
    - "incrementally computing minimal unsatisfiable cores of qbfs via a clause group solver api"
    - "conformant planning as a case study of incremental qbf solving"
    - "incremental qbf solving"
    - "computing resolution path dependencies in linear time"
    - "clause term resolution and learning in the evaluation of quantified boolean formulas"

Connected through hyperedge HE-4 (induced by source paper "q resolution with generalized axioms"):
  with members:
    - "clause term resolution and learning in the evaluation of quantified boolean formulas"

Connected through hyperedge HE-5 (induced by source paper "machine learning with guarantees using descriptive complexity and smt solvers"):
  with members:
    - "solving and verifying the boolean pythagorean triples problem via cube and conquer"

Question: Please tell me which class the center node belongs to. The 40 classes are: cs.NA(Numerical Analysis), cs.MM(Multimedia), cs.LO(Logic in Computer Science), cs.CY(Computers and Society), cs.CR(Cryptography and Security), cs.DC(Distributed, Parallel, and Cluster Computing), cs.HC(Human-Computer Interaction), cs.CE(Computational Engineering, Finance, and Science), cs.NI(Networking and Internet Architecture), cs.CC(Computational Complexity), cs.AI(Artificial Intelligence), cs.MA(Multiagent Systems), cs.GL(General Literature), cs.NE(Neural and Evolutionary Computing), cs.SC(Symbolic Computation), cs.AR(Hardware Architecture), cs.CV(Computer Vision and Pattern Recognition), cs.GR(Graphics), cs.ET(Emerging Technologies), cs.SY(Systems and Control), cs.CG(Computational Geometry), cs.OH(Other Computer Science), cs.PL(Programming Languages), cs.SE(Software Engineering), cs.LG(Machine Learning), cs.SD(Sound), cs.SI(Social and Information Networks), cs.RO(Robotics), cs.IT(Information Theory), cs.PF(Performance), cs.CL(Computation and Language), cs.IR(Information Retrieval), cs.MS(Mathematical Software), cs.FL(Formal Languages and Automata Theory), cs.DS(Data Structures and Algorithms), cs.OS(Operating Systems), cs.GT(Computer Science and Game Theory), cs.DB(Databases), cs.DL(Digital Libraries), cs.DM(Discrete Mathematics). Directly output the class name.

gpt: cs.LO(Logic in Computer Science)