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 proof of csp dichotomy conjecture"
  Abstract: Many natural combinatorial problems can be expressed as constraint satisfaction problems. This class of problems is known to be NP-complete in general, but certain restrictions on the form of the constraints can ensure tractability. The standard way to parameterize interesting subclasses of the constraint satisfaction problem is via finite constraint languages. The main problem is to classify those subclasses that are solvable in polynomial time and those that are NP-complete. It was conjectured that if a core of a constraint language has a weak near unanimity polymorphism then the corresponding constraint satisfaction problem is tractable, otherwise it is NP-complete. #R##N#In the paper we present an algorithm that solves Constraint Satisfaction Problem in polynomial time for constraint languages having a weak near unanimity polymorphism, which proves the remaining part of the conjecture.

Connected through hyperedge HE-1 (induced by source paper "optimal polynomial time compression for boolean max csp"):
  with members:
    - "a dichotomy theorem for nonuniform csps"
    - "kernelization of constraint satisfaction problems a study through universal algebra"
    - "tight hardness for shortest cycles and paths in sparse graphs"
    - "sparsification upper and lower bounds for graph problems and not all equal sat"
    - "complexity of counting csp with complex weights"
    - "preprocessing of min ones problems a dichotomy"
    - "the approximability of max csp with fixed value constraints"

Connected through hyperedge HE-2 (induced by source paper "topology is relevant in a dichotomy conjecture for infinite domain constraint satisfaction problems"):
  with members:
    - "a universal algebraic proof of the complexity dichotomy for monotone monadic snp"
    - "algebraic approach to promise constraint satisfaction"
    - "a dichotomy theorem for nonuniform csps"
    - "constraint satisfaction problems for reducts of homogeneous graphs"
    - "the algebraic dichotomy conjecture for infinite domain constraint satisfaction problems"
    - "a complexity dichotomy for poset constraint satisfaction"
    - "equations in oligomorphic clones and the constraint satisfaction problem for omega categorical structures"
    - "the complexity of phylogeny constraint satisfaction problems"

Connected through hyperedge HE-3 (induced by source paper "the complexity of boolean surjective general valued csps"):
  with members:
    - "a dichotomy theorem for nonuniform csps"
    - "the complexity of finite valued csps"
    - "a galois connection for weighted relational clones of infinite size"
    - "algebraic properties of valued constraint satisfaction problem"
    - "the complexity of general valued csps"
    - "an algebraic hardness criterion for surjective constraint satisfaction"
    - "an algebraic theory of complexity for discrete optimization"
    - "on the approximation of submodular functions"

Connected through hyperedge HE-4 (induced by source paper "approximate counting csp seen from the other side"):
  with members:
    - "constraint solving via fractional edge covers"
    - "a dichotomy theorem for nonuniform csps"
    - "approximately counting h colourings is bis hard"
    - "the complexity of approximating conservative counting csps"
    - "the challenges of unbounded treewidth in parameterised subgraph counting problems"
    - "understanding model counting for beta acyclic cnf formulas"
    - "complexity of counting csp with complex weights"
    - "an effective dichotomy for the counting constraint satisfaction problem"

Connected through hyperedge HE-5 (induced by source paper "qcsp monsters and the demise of the chen conjecture"):
  with members:
    - "a dichotomy theorem for nonuniform csps"
    - "the complexity of quantified constraints using the algebraic formulation"
    - "the algebraic dichotomy conjecture for infinite domain constraint satisfaction problems"
    - "quantified constraints and containment problems"
    - "the complexity of general valued csps"
    - "from complexity to algebra and back digraph classes collapsibility and the pgp"
    - "on the complexity of the model checking problem"
    - "meditations on quantified constraint satisfaction"

Connected through hyperedge HE-6 (induced by source paper "the complexity of 3 colouring h colourable graphs"):
  with members:
    - "improved hardness for h colourings of g colourable graphs"
    - "simplified inpproximability of hypergraph coloring via t agreeing families"
    - "an algorithmic blend of lps and ring equations for promise csps"
    - "improved inapproximability of rainbow coloring"
    - "algebraic approach to promise constraint satisfaction"
    - "a dichotomy theorem for nonuniform csps"
    - "robustly solvable constraint satisfaction problems"
    - "improved hardness of approximating chromatic number"

Connected through hyperedge HE-7 (induced by source paper "point width and max csps"):
  with members:
    - "understanding the complexity of sat using knowledge compilation"
    - "constraint solving via fractional edge covers"
    - "the complexity of general valued csps seen from the other side"
    - "a dichotomy theorem for nonuniform csps"
    - "the complexity of finite valued csps"
    - "general and fractional hypertree decompositions hard and easy cases"
    - "understanding model counting for beta acyclic cnf formulas"
    - "tractable optimization problems through hypergraph based structural restrictions"

Connected through hyperedge HE-8 (induced by source paper "global cardinality constraints make approximating some max 2 csps harder"):
  with members:
    - "resolution lower bounds for refutation statements"
    - "a note on max k vertex cover faster fpt as smaller approximate kernel and improved approximation"
    - "a dichotomy theorem for nonuniform csps"
    - "analysis of boolean functions"
    - "better balance by being biased a 0 8776 approximation for max bisection"
    - "approximating csps with global cardinality constraints using sdp hierarchies"
    - "the complexity of global cardinality constraints"
    - "conditional hardness for approximate coloring"

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)