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: "an infinite class of sparse yao spanners"
  Abstract: We show that, for any integer k > 5, the Sparse-Yao graph YY_{6k} (also known as Yao-Yao) is a spanner with stretch factor 11.67. The stretch factor drops down to 4.75 for k > 7.

Connected through hyperedge HE-1 (induced by source paper "truly optimal euclidean spanners"):
  with members:
    - "on the spanning and routing ratio of theta four"
    - "odd yao yao graphs are not spanners"
    - "greedy spanners are optimal in doubling metrics"
    - "minor free graphs have light spanners"
    - "the greedy spanner is existentially optimal"
    - "almost all even yao yao graphs are spanners"
    - "a light metric spanner"
    - "upper bounds on the spanning ratio of constrained theta graphs"

Connected through hyperedge HE-2 (induced by source paper "spanning properties of theta theta 6"):
  with members:
    - "on the spanning and routing ratio of theta four"
    - "odd yao yao graphs are not spanners"
    - "almost all even yao yao graphs are spanners"
    - "the θ 5 graph is a spanner"
    - "towards tight bounds on theta graphs"
    - "new and improved spanning ratios for yao graphs"
    - "π 2 angle yao graphs are spanners"

Connected through hyperedge HE-3 (induced by source paper "almost all even yao yao graphs are spanners"):
  with members:
    - "new and improved spanning ratios for yao graphs"
    - "π 2 angle yao graphs are spanners"
    - "a simple yao yao based spanner of bounded degree"
    - "on the stretch factor of convex delaunay graphs"

Connected through hyperedge HE-4 (induced by source paper "spanning properties of theta theta graphs"):
  with members:
    - "the θ 5 graph is a spanner"
    - "towards tight bounds on theta graphs"
    - "the yao graph y_5 is a spanner"
    - "new and improved spanning ratios for yao graphs"
    - "on the stretch factor of the theta 4 graph"
    - "π 2 angle yao graphs are spanners"

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)