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 "pixel and voxel representations of graphs"):
  Abstract: We study contact representations for graphs, which we call pixel representations in 2D and voxel representations in 3D. Our representations are based on the unit square grid whose cells we call pixels in 2D and voxels in 3D. Two pixels are adjacent if they share an edge, two voxels if they share a face. We call a connected set of pixels or voxels a blob. Given a graph, we represent its vertices by disjoint blobs such that two blobs contain adjacent pixels or voxels if and only if the corresponding vertices are adjacent. We are interested in the size of a representation, which is the number of pixels or voxels it consists of. #R##N#We first show that finding minimum-size representations is NP-complete. Then, we bound representation sizes needed for certain graph classes. In 2D, we show that, for $k$-outerplanar graphs with $n$ vertices, $\Theta(kn)$ pixels are always sufficient and sometimes necessary. In particular, outerplanar graphs can be represented with a linear number of pixels, whereas general planar graphs sometimes need a quadratic number. In 3D, $\Theta(n^2)$ voxels are always sufficient and sometimes necessary for any $n$-vertex graph. We improve this bound to $\Theta(n\cdot \tau)$ for graphs of treewidth $\tau$ and to $O((g+1)^2n\log^2n)$ for graphs of genus $g$. In particular, planar graphs admit representations with $O(n\log^2n)$ voxels.

Includes members:
  Member "1 visibility representations of 1 planar graphs":
    also connected through other hyperedges:
      - Hyperedge HE-1 (induced by source paper "fan crossing free graphs")
  Member "bar 1 visibility graphs and their relation to other nearly planar graphs":
    also connected through other hyperedges:
      - Hyperedge HE-2 (induced by source paper "a survey on graph drawing beyond planarity")
  Member "equilateral l contact graphs":
    also connected through other hyperedges:
      - Hyperedge HE-3 (induced by source paper "cpg graphs some structural and hardness results")
  Member "on triangulating k outerplanar graphs":
    also connected through other hyperedges:
      - Hyperedge HE-4 (induced by source paper "detecting and counting small patterns in planar graphs in subexponential parameterized time")
  Member "computing cartograms with optimal complexity":
    also connected through other hyperedges:
      - Hyperedge HE-5 (induced by source paper "homothetic triangle representations of planar graphs")
  Member "optimal polygonal representation of planar graphs":
    also connected through other hyperedges:
      - Hyperedge HE-6 (induced by source paper "homothetic triangle representations of planar graphs")
  Member "rectangular layouts and contact graphs":
    also connected through other hyperedges:
      - Hyperedge HE-7 (induced by source paper "triangle free penny graphs degeneracy choosability and edge count")

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.DM(Discrete Mathematics)