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: "backdoors to tractable answer set programming"
  Abstract: Answer Set Programming (ASP) is an increasingly popular framework for declarative programming that admits the description of problems by means of rules and constraints that form a disjunctive logic program. In particular, many AI problems such as reasoning in a nonmonotonic setting can be directly formulated in ASP. Although the main problems of ASP are of high computational complexity, located at the second level of the Polynomial Hierarchy, several restrictions of ASP have been identified in the literature, under which ASP problems become tractable. #R##N#In this paper we use the concept of backdoors to identify new restrictions that make ASP problems tractable. Small backdoors are sets of atoms that represent "clever reasoning shortcuts" through the search space and represent a hidden structure in the problem input. The concept of backdoors is widely used in the areas of propositional satisfiability and constraint satisfaction. We show that it can be fruitfully adapted to ASP. We demonstrate how backdoors can serve as a unifying framework that accommodates several tractable restrictions of ASP known from the literature. Furthermore, we show how backdoors allow us to deploy recent algorithmic results from parameterized complexity theory to the domain of answer set programming.

Connected through hyperedge HE-1 (induced by source paper "structural decompositions of epistemic logic programs"):
  with members:
    - "epistemic logic programs a different world view"
    - "treewidth and counting projected answer sets"
    - "te eth lower bounds for qbfs of bounded treewidth"
    - "splitting epistemic logic programs"
    - "answer set solving with bounded treewidth revisited"
    - "the power of non ground rules in answer set programming"
    - "combining treewidth and backdoors for csp"
    - "clique width and directed width measures for answer set programming"

Connected through hyperedge HE-2 (induced by source paper "te eth lower bounds for qbfs of bounded treewidth"):
  with members:
    - "treewidth and counting projected answer sets"
    - "exploiting treewidth for projected model counting and its limits"
    - "counting complexity for reasoning in abstract argumentation"
    - "qbf as an alternative to courcelle s theorem"
    - "evaluating qbf solvers quantifier alternations matter"
    - "slightly superexponential parameterized problems"
    - "parameterized complexity results for exact bayesian network structure learning"

Connected through hyperedge HE-3 (induced by source paper "a paraconsistent asp like language with tractable model generation"):
  with members:
    - "answer set solving with bounded treewidth revisited"
    - "logical foundations and complexity of 4ql a query language with unrestricted negation"
    - "the dlv system for knowledge representation and reasoning"
    - "a hierarchy of tractable subsets for computing stable models"

Connected through hyperedge HE-4 (induced by source paper "answer set solving with bounded treewidth revisited"):
  with members:
    - "tractable answer set programming with weight constraints bounded treewidth is not enough"

Connected through hyperedge HE-5 (induced by source paper "backdoors to tractable valued csp"):
  with members:
    - "the complexity landscape of decompositional parameters for ilp"
    - "differential game logic"
    - "necessary conditions for tractability of valued csps"
    - "discovering archipelagos of tractability for constraint satisfaction and counting"
    - "on backdoors to tractable constraint languages"
    - "the complexity of conservative valued csps"
    - "backdoors to normality for disjunctive logic programs"
    - "backdoors to satisfaction"

Connected through hyperedge HE-6 (induced by source paper "strong backdoors for linear temporal logic"):
  with members:
    - "ltl fragments are hard for standard parameterisations"
    - "backdoors to normality for disjunctive logic programs"
    - "satisfiability of acyclic and almost acyclic cnf formulas"
    - "the complexity of clausal fragments of ltl"
    - "backdoors to satisfaction"
    - "the complexity of generalized satisfiability for linear temporal logic"
    - "clausal temporal resolution"

Connected through hyperedge HE-7 (induced by source paper "clique width and directed width measures for answer set programming"):
  with members:
    - "directed width measures and monotonicity of directed graph searching"
    - "a trichotomy for regular simple path queries on graphs"
    - "digraph complexity measures and applications in formal language theory"
    - "trichotomy and dichotomy results on the complexity of reasoning with disjunctive logic programs"
    - "fixed parameter complexity of semantics for logic programs"
    - "a hierarchy of tractable subsets for computing stable models"

Connected through hyperedge HE-8 (induced by source paper "strong backdoors for default logic"):
  with members:
    - "backdoors to normality for disjunctive logic programs"
    - "satisfiability of acyclic and almost acyclic cnf formulas"
    - "backdoors to abduction"
    - "backdoors to satisfaction"
    - "the complexity of propositional implication"

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.CC(Computational Complexity)