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: "efficient computation of visibility polygons"
  Abstract: Determining visibility in planar polygons and arrangements is an important subroutine for many algorithms in computational geometry. In this paper, we report on new implementations, and corresponding experimental evaluations, for two established and one novel algorithm for computing visibility polygons. These algorithms will be released to the public shortly, as a new package for the Computational Geometry Algorithms Library (CGAL).

Connected through hyperedge HE-1 (induced by source paper "the continuous 1 5d terrain guarding problem discretization optimal solutions and ptas"):
  with members:
    - "engineering art galleries"
    - "algorithms for art gallery illumination"
    - "a ptas for the continuous 1 5d terrain guarding problem"
    - "facets for art gallery problems"
    - "terrain visibility with multiple viewpoints"
    - "a generic lazy evaluation scheme for exact geometric computations"
    - "improved approximation algorithms for geometric set cover"

Connected through hyperedge HE-2 (induced by source paper "engineering art galleries"):
  with members:
    - "algorithms for art gallery illumination"
    - "facets for art gallery problems"
    - "a generic lazy evaluation scheme for exact geometric computations"

Connected through hyperedge HE-3 (induced by source paper "algorithms for art gallery illumination"):
  with members:
    - "engineering art galleries"
    - "facets for art gallery 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.CG(Computational Geometry)