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: "a characterization of approximation resistance for even k partite csps"
  Abstract: A constraint satisfaction problem (CSP) is said to be \emph{approximation resistant} if it is hard to approximate better than the trivial algorithm which picks a uniformly random assignment. Assuming the Unique Games Conjecture, we give a characterization of approximation resistance for $k$-partite CSPs defined by an even predicate.

Connected through hyperedge HE-1 (induced by source paper "on the approximation resistance of balanced linear threshold functions"):
  with members:
    - "a dichotomy theorem for nonuniform csps"
    - "sum of squares lower bounds for refuting any csp"
    - "a characterization of approximation resistance"
    - "on the usefulness of predicates"
    - "approximation resistant predicates from pairwise independence"

Connected through hyperedge HE-2 (induced by source paper "complexity and approximability of parameterized max csps"):
  with members:
    - "solving maxsat and sat on structured cnf formulas"
    - "tractable answer set programming with weight constraints bounded treewidth is not enough"
    - "guarantees and limits of preprocessing in constraint satisfaction and reasoning"
    - "model counting for formulas of bounded clique width"
    - "satisfiability of acyclic and almost acyclic cnf formulas"
    - "majority is stablest discrete and sos"
    - "backdoors to acyclic sat"
    - "not so easy problems for tree decomposable graphs"

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)