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 complexity of parity graph homomorphism an initial investigation"
  Abstract: Given a graph G, we investigate the question of determining the parity of the number of homomorphisms from G to some other fixed graph H. We conjecture that this problem exhibits a complexity dichotomy, such that all parity graph homomorphism problems are either polynomial-time solvable or parityP-complete, and provide a conjectured characterisation of the easy cases. #R##N#We show that the conjecture is true for the restricted case in which the graph H is a tree, and provide some tools that may be useful in further investigation into the parity graph homomorphism problem, and the problem of counting homomorphisms for other moduli.

Connected through hyperedge HE-1 (induced by source paper "counting homomorphisms modulo a prime number"):
  with members:
    - "counting homomorphisms to trees modulo a prime"
    - "inapproximability of the independent set polynomial in the complex plane"
    - "counting homomorphisms to square free graphs modulo 2"
    - "the complexity of counting homomorphisms to cactus graphs modulo 2"
    - "graph homomorphisms with complex values a dichotomy theorem"
    - "a complexity dichotomy for partition functions with mixed signs"

Connected through hyperedge HE-2 (induced by source paper "counting homomorphisms to trees modulo a prime"):
  with members:
    - "counting homomorphisms to square free graphs modulo 2"
    - "the complexity of counting solutions to generalised satisfiability problems modulo k"
    - "a complexity dichotomy for partition functions with mixed signs"

Connected through hyperedge HE-3 (induced by source paper "counting homomorphisms to square free graphs modulo 2"):
  with members:
    - "the complexity of counting homomorphisms to cactus graphs modulo 2"
    - "approximately counting locally optimal structures"
    - "a complexity dichotomy for partition functions with mixed signs"

Connected through hyperedge HE-4 (induced by source paper "the complexity of counting homomorphisms to cactus graphs modulo 2"):
  with members:
    - "graph homomorphisms with complex values a dichotomy theorem"
    - "the complexity of weighted boolean csp"
    - "the complexity of counting solutions to generalised satisfiability problems modulo k"
    - "a complexity dichotomy for partition functions with mixed signs"

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)