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: "surjective h colouring new hardness results"
  Abstract: A homomorphism from a graph G to a graph H is a vertex mapping f from the vertex set of G to the vertex set of H such that there is an edge between vertices f(u) and f(v) of H whenever there is an edge between vertices u and v of G. The H-Colouring problem is to decide whether or not a graph G allows a homomorphism to a fixed graph H. We continue a study on a variant of this problem, namely the Surjective H-Colouring problem, which imposes the homomorphism to be vertex-surjective. We build upon previous results and show that this problem is NP-complete for every connected graph H that has exactly two vertices with a self-loop as long as these two vertices are not adjacent. As a result, we can classify the computational complexity of Surjective H-Colouring for every graph H on at most four vertices.

Connected through hyperedge HE-1 (induced by source paper "the complexity of approximately counting retractions"):
  with members:
    - "a dichotomy theorem for nonuniform csps"
    - "approximately counting h colourings is bis hard"
    - "the complexity of approximately counting tree homomorphisms"
    - "ferromagnetic potts model refined bis hardness and related results"
    - "the complexity of surjective homomorphism problems a survey"
    - "an approximation trichotomy for boolean csp"

Connected through hyperedge HE-2 (induced by source paper "the complexity of counting surjective homomorphisms and compactions"):
  with members:
    - "homomorphisms are a good basis for counting small subgraphs"
    - "homomorphisms are indeed a good basis for counting three fixed template dichotomy theorems for the price of one"
    - "note on the complexity of counting surjective homomorphisms and compactions"
    - "counting homomorphisms to square free graphs modulo 2"
    - "finding vertex surjective graph homomorphisms"
    - "the complexity of surjective homomorphism problems a survey"

Connected through hyperedge HE-3 (induced by source paper "surjective h colouring over reflexive digraphs"):
  with members:
    - "a dichotomy theorem for nonuniform csps"
    - "the proof of csp dichotomy conjecture"
    - "an algebraic hardness criterion for surjective constraint satisfaction"
    - "the complexity of surjective homomorphism problems a survey"
    - "a characterisation of first order constraint satisfaction problems"

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)