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: "circle packing for origami design is hard"
  Abstract: We show that deciding whether a given set of circles can be packed into a rectangle, an equilateral triangle, or a unit square are NP-hard problems, settling the complexity of these natural packing problems. On the positive side, we show that any set of circles of total area 1 can be packed into a square of size 4/\sqrt{pi}=2.2567... These results are motivated by problems arising in the context of origami design.

Connected through hyperedge HE-1 (induced by source paper "worst case optimal covering of rectangles by disks"):
  with members:
    - "split packing algorithms for packing circles with optimal worst case density"
    - "a constant factor approximation for multi covering with disks"
    - "covering a line segment with variable radius discs"

Connected through hyperedge HE-2 (induced by source paper "online circle packing"):
  with members:
    - "packing disks into disks with optimal worst case density"
    - "split packing algorithms for packing circles with optimal worst case density"
    - "online square into square packing"
    - "improved online square into square packing"

Connected through hyperedge HE-3 (induced by source paper "resilience by reconfiguration exploiting heterogeneity in robot teams"):
  with members:
    - "graph drawing by stochastic gradient descent"
    - "robustness of information diffusion algorithms to locally bounded adversaries"

Connected through hyperedge HE-4 (induced by source paper "packing disks into disks with optimal worst case density"):
  with members:
    - "split packing algorithms for packing circles with optimal worst case density"

Connected through hyperedge HE-5 (induced by source paper "placing your coins on a shelf"):
  with members:
    - "the triangle scheduling problem"
    - "recognizing weighted disk contact graphs"

Connected through hyperedge HE-6 (induced by source paper "online circle and sphere packing"):
  with members:
    - "on limits of dense packing of equal spheres in a cube"
    - "polynomial time approximation schemes for circle and other packing problems"

Connected through hyperedge HE-7 (induced by source paper "an example of geometric origami design with benefit of graph enumeration algorithms"):
  with members:
    - "filling a hole in a crease pattern isometric mapping from prescribed boundary folding"

Connected through hyperedge HE-8 (induced by source paper "online square into square packing"):
  with members:
    - "online square packing"

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)