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: "necessary conditions for tractability of valued csps"
  Abstract: The connection between constraint languages and clone theory has been a fruitful line of research on the complexity of constraint satisfaction problems. In a recent result, Cohen et al. [SIAM J. Comput., 42 (2013), pp. 915--1939] have characterized a Galois connection between valued constraint languages and so-called weighted clones. In this paper, we study the structure of weighted clones. We extend the results of Creed and Živný from [Proceedings of the 17th International Conference on Principles and Practice of Constraint Programming, 2011, pp. 210--224] on types of weightings necessarily contained in every nontrivial weighted clone. This result has immediate computational complexity consequences as it provides necessary conditions for tractability of weighted clones and thus valued constraint languages. We demonstrate that some of the necessary conditions are also sufficient for tractability, while others are provably not.

Connected through hyperedge HE-1 (induced by source paper "representing fitness landscapes by valued constraints to understand the complexity of local search"):
  with members:
    - "the complexity of general valued csps seen from the other side"
    - "the complexity of finite valued csps"
    - "an algebraic theory of complexity for discrete optimization"
    - "the complexity of conservative valued csps"

Connected through hyperedge HE-2 (induced by source paper "on planar valued csps"):
  with members:
    - "the power of sherali adams relaxations for general valued csps"
    - "even delta matroids and the complexity of planar boolean csps"
    - "the complexity of finite valued csps"
    - "a galois connection for weighted relational clones of infinite size"
    - "hybrid v csps and algebraic reductions"
    - "algebraic properties of valued constraint satisfaction problem"
    - "the complexity of general valued csps"
    - "effectiveness of structural restrictions for hybrid csps"

Connected through hyperedge HE-3 (induced by source paper "a galois connection for weighted relational clones of infinite size"):
  with members:
    - "the power of sherali adams relaxations for general valued csps"
    - "the complexity of finite valued csps"
    - "algebraic properties of valued constraint satisfaction problem"
    - "the complexity of general valued csps"
    - "sherali adams relaxations for valued csps"
    - "an algebraic theory of complexity for discrete optimization"
    - "the complexity of conservative valued csps"
    - "the power of linear programming for general valued csps"

Connected through hyperedge HE-4 (induced by source paper "backdoors to tractable valued csp"):
  with members:
    - "the complexity landscape of decompositional parameters for ilp"
    - "differential game logic"
    - "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"
    - "backdoors to tractable answer set programming"

Connected through hyperedge HE-5 (induced by source paper "sherali adams relaxations for valued csps"):
  with members:
    - "algebraic properties of valued constraint satisfaction problem"
    - "local distribution and the symmetry gap approximability of multiway partitioning problems"
    - "the complexity of conservative valued csps"
    - "the power of linear programming for general valued csps"
    - "the power of linear programming for valued csps"
    - "an effective fusion technique of cloud computing and networking series"
    - "extensions of the minimum cost homomorphism problem"

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)