human: Given a hyperedge-centered hypergraph: <hypergraph>, where the center hyperedge is induced by one source paper and its member nodes are the cited papers.

Details of the hypergraph:
Center hyperedge (induced by source paper "the parameterized complexity of guarding almost convex polygons"):
  Abstract: Art Gallery is a fundamental visibility problem in Computational Geometry. The input consists of a simple polygon P, (possibly infinite) sets G and C of points within P, and an integer k; the task is to decide if at most k guards can be placed on points in G so that every point in C is visible to at least one guard. In the classic formulation of Art Gallery, G and C consist of all the points within P. Other well-known variants restrict G and C to consist either of all the points on the boundary of P or of all the vertices of P. Recently, three new important discoveries were made: the above mentioned variants of Art Gallery are all W[1]-hard with respect to k [Bonnet and Miltzow, ESA'16], the classic variant has an O(log k)-approximation algorithm [Bonnet and Miltzow, SoCG'17], and it may require irrational guards [Abrahamsen et al., SoCG'17]. Building upon the third result, the classic variant and the case where G consists only of all the points on the boundary of P were both shown to be \exists R-complete~[Abrahamsen et al., STOC'18]. Even when both G and C consist only of all the points on the boundary of P, the problem is not known to be in NP. #R##N#Given the first discovery, the following question was posed by Giannopoulos [Lorentz Center Workshop, 2016]: Is Art Gallery FPT with respect to r, the number of reflex vertices? We focus on the variant where G and C are all the vertices of P, called Vertex-Vertex Art Gallery. We show that Vertex-Vertex Art Gallery is solvable in time r^{O(r^2)}n^{O(1)}. Our approach also extends to assert that Vertex-Boundary Art Gallery and Boundary-Vertex Art Gallery are both FPT. We utilize structural properties of "almost convex polygons" to present a two-stage reduction from Vertex-Vertex Art Gallery to a new constraint satisfaction problem (whose solution is also provided in this paper) where constraints have arity 2 and involve monotone functions.

Includes members:
  Member "a ptas for vertex guarding weakly visible polygons an extended abstract":
    also connected through other hyperedges:
      - Hyperedge HE-1 (induced by source paper "a constant factor approximation algorithm for vertex guarding a wv polygon")
  Member "constant approximation algorithms for guarding simple polygons using vertex guards":
    also connected through other hyperedges:
      - Hyperedge HE-2 (induced by source paper "routing in histograms")
  Member "irrational guards are sometimes needed":
    also connected through other hyperedges:
      - Hyperedge HE-3 (induced by source paper "smoothed analysis of the art gallery problem")
  Member "an approximation algorithm for the art gallery problem":
    also connected through other hyperedges:
      - Hyperedge HE-4 (induced by source paper "a constant factor approximation algorithm for vertex guarding a wv polygon")
  Member "engineering art galleries":
    also connected through other hyperedges:
      - Hyperedge HE-5 (induced by source paper "smoothed analysis of the art gallery problem")
  Member "approximability of guarding weak visibility polygons":
    also connected through other hyperedges:
      - Hyperedge HE-6 (induced by source paper "routing in histograms")
  Member "a new upper bound for the vc dimension of visibility regions":
    also connected through other hyperedges:
      - Hyperedge HE-7 (induced by source paper "the vc dimension of metric balls under fr echet and hausdorff distances")
  Member "improved approximation for guarding simple galleries from the perimeter":
    also connected through other hyperedges:
      - Hyperedge HE-8 (induced by source paper "a constant factor approximation algorithm for vertex guarding a wv polygon")

Question: Please tell me which class the source paper 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)