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: "improved approximation for guarding simple galleries from the perimeter"
  Abstract: We provide an O(log log OPT)-approximation algorithm for the problem of guarding a simple polygon with guards on the perimeter. We first design a polynomial-time algorithm for building epsilon-nets of size O(1/epsilon log log 1/epsilon) for the instances of Hitting Set associated with our guarding problem. We then apply the technique of Bronnimann and Goodrich to build an approximation algorithm from this epsilon-net finder. Along with a simple polygon P, our algorithm takes as input a finite set of potential guard locations that must include the polygon's vertices. If a finite set of potential guard locations is not specified, e.g. when guards may be placed anywhere on the perimeter, we use a known discretization technique at the cost of making the algorithm's running time potentially linear in the ratio between the longest and shortest distances between vertices. Our algorithm is the first to improve upon O(log OPT)-approximation algorithms that use generic net finders for set systems of finite VC-dimension.

Connected through hyperedge HE-1 (induced by source paper "the parameterized complexity of guarding almost convex polygons"):
  with members:
    - "a ptas for vertex guarding weakly visible polygons an extended abstract"
    - "constant approximation algorithms for guarding simple polygons using vertex guards"
    - "irrational guards are sometimes needed"
    - "an approximation algorithm for the art gallery problem"
    - "engineering art galleries"
    - "approximability of guarding weak visibility polygons"
    - "a new upper bound for the vc dimension of visibility regions"
    - "unsolved problems in visibility graphs of points segments and polygons"

Connected through hyperedge HE-2 (induced by source paper "a constant factor approximation algorithm for vertex guarding a wv polygon"):
  with members:
    - "a ptas for vertex guarding weakly visible polygons an extended abstract"
    - "constant approximation algorithms for guarding simple polygons using vertex guards"
    - "an approximation algorithm for the art gallery problem"
    - "the continuous 1 5d terrain guarding problem discretization optimal solutions and ptas"
    - "approximability of guarding weak visibility polygons"

Connected through hyperedge HE-3 (induced by source paper "on conflict free chromatic guarding of simple polygons"):
  with members:
    - "a ptas for vertex guarding weakly visible polygons an extended abstract"
    - "an approximation algorithm for the art gallery problem"
    - "approximability of guarding weak visibility polygons"

Connected through hyperedge HE-4 (induced by source paper "epsilon approximations and epsilon nets"):
  with members:
    - "near optimal epsilon kernel construction and related problems"
    - "a size sensitive discrepancy bound for set systems of bounded primal shatter dimension"
    - "small strong epsilon nets"
    - "constructive discrepancy minimization by walking on the edges"
    - "a unified framework for approximating and clustering data"
    - "tight lower bounds for the size of epsilon nets"
    - "algorithms for eps approximations of terrains"
    - "improved approximation algorithms for geometric set cover"

Connected through hyperedge HE-5 (induced by source paper "constant approximation algorithms for guarding simple polygons using vertex guards"):
  with members:
    - "a ptas for vertex guarding weakly visible polygons an extended abstract"
    - "an approximation algorithm for the art gallery problem"
    - "vertex guarding in weak visibility polygons"

Connected through hyperedge HE-6 (induced by source paper "exact vc dimension for l_1 visibility of points in simple polygons"):
  with members:
    - "a new upper bound for the vc dimension of visibility regions"

Connected through hyperedge HE-7 (induced by source paper "finding small hitting sets in infinite range spaces of bounded vc dimension"):
  with members:
    - "a new upper bound for the vc dimension of visibility regions"
    - "geometric set cover and hitting sets for polytopes in r 3"

Connected through hyperedge HE-8 (induced by source paper "universal guard problems"):
  with members:
    - "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)