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: "weight constraints as nested expressions"
  Abstract: We compare two recent extensions of the answer set (stable model) semantics of logic programs. One of them, due to Lifschitz, Tang and Turner, allows the bodies and heads of rules to contain nested expressions. The other, due to Niemela and Simons, uses weight constraints. We show that there is a simple, modular translation from the language of weight constraints into the language of nested expressions that preserves the program's answer sets. Nested expressions can be eliminated from the result of this translation in favor of additional atoms. The translation makes it possible to compute answer sets for some programs with weight constraints using satisfiability solvers, and to prove the strong equivalence of programs with weight constraints using the logic of here-and there.

Connected through hyperedge HE-1 (induced by source paper "strong equivalence and program s structure in arguing essential equivalence between logic programs"):
  with members:
    - "abstract gringo"
    - "first order modular logic programs and their conservative extensions"
    - "lpopt a rule optimization tool for answer set programming"
    - "modularity aspects of disjunctive stable models"
    - "a common view on strong uniform and other notions of equivalence in answer set programming"

Connected through hyperedge HE-2 (induced by source paper "shared aggregate sets in answer set programming"):
  with members:
    - "asp core 2 input language format"
    - "constraints lazy constraints or propagators in asp solving an empirical analysis"
    - "clingcon the next generation"
    - "combining answer set programming and domain heuristics for solving hard industrial problems application paper"
    - "anytime answer set optimization via unsatisfiable core shrinking"
    - "predicate logic as a modeling language modeling and solving some machine learning and data mining problems with idp3"
    - "complexity and compilation of gz aggregates in answer set programming"
    - "rewriting recursive aggregates in answer set programming back to monotonicity"

Connected through hyperedge HE-3 (induced by source paper "abstract gringo"):
  with members:
    - "asp core 2 input language format"
    - "on equivalence of infinitary formulas under the stable model semantics"
    - "lloyd topor completion and general stable models"

Connected through hyperedge HE-4 (induced by source paper "constraint answer set solver ezcsp and why integration schemas matter"):
  with members:
    - "the language features and architecture of b prolog"
    - "a translational approach to constraint answer set solving"
    - "sicstus prolog the first 25 years"
    - "efficient constraint propagation engines"
    - "stable models and an alternative logic programming paradigm"

Connected through hyperedge HE-5 (induced by source paper "on relation between constraint answer set programming and satisfiability modulo theories"):
  with members:
    - "constraint answer set solver ezcsp and why integration schemas matter"
    - "conflict driven asp solving with external sources"
    - "transition systems for model generators a unifying approach"
    - "the language features and architecture of b prolog"

Connected through hyperedge HE-6 (induced by source paper "vicious circle principle and formation of sets in asp based languages"):
  with members:
    - "complexity and compilation of gz aggregates in answer set programming"
    - "rewriting recursive aggregates in answer set programming back to monotonicity"
    - "vicious circle principle and logic programs with aggregates"
    - "characterizations of stable model semantics for logic programs with arbitrary constraint atoms"
    - "well founded and stable semantics of logic programs with aggregates"

Connected through hyperedge HE-7 (induced by source paper "rewriting recursive aggregates in answer set programming back to monotonicity"):
  with members:
    - "anytime computation of cautious consequences in answer set programming"
    - "vicious circle principle and logic programs with aggregates"
    - "conflict driven asp solving with external sources"
    - "unfounded sets and well founded semantics of answer set programs with aggregates"
    - "relating weight constraint and aggregate programs semantics and representation"
    - "logic programs with propositional connectives and aggregates"
    - "design and implementation of aggregate functions in the dlv system"
    - "properties and applications of programs with monotone and convex constraints"

Connected through hyperedge HE-8 (induced by source paper "generating explanations for biomedical queries"):
  with members:
    - "team building with answer set programming in the gioia tauro seaport"
    - "catching the ouroboros on debugging non ground answer set programs"
    - "justifications for logic programs under answer set semantics"
    - "stable models and an alternative logic programming paradigm"

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.AI(Artificial Intelligence)