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 "spanning properties of theta theta 6"):
  Abstract: We show that, unlike the Yao-Yao graph $YY_6$, the Theta-Theta graph $\Theta\Theta_6$ defined by six cones is a spanner for sets of points in convex position. We also show that, for sets of points in non-convex position, the spanning ratio of $\Theta\Theta_6$ is unbounded.

Includes members:
  Member "on the spanning and routing ratio of theta four":
    also connected through other hyperedges:
      - Hyperedge HE-1 (induced by source paper "truly optimal euclidean spanners")
  Member "odd yao yao graphs are not spanners":
    also connected through other hyperedges:
      - Hyperedge HE-2 (induced by source paper "truly optimal euclidean spanners")
  Member "almost all even yao yao graphs are spanners":
    also connected through other hyperedges:
      - Hyperedge HE-3 (induced by source paper "truly optimal euclidean spanners")
  Member "the θ 5 graph is a spanner":
    also connected through other hyperedges:
      - Hyperedge HE-4 (induced by source paper "maximum matchings and minimum blocking sets in θ 6 graphs")
  Member "towards tight bounds on theta graphs":
    also connected through other hyperedges:
      - Hyperedge HE-5 (induced by source paper "expected complexity of routing in theta 6 and half theta 6 graphs")
  Member "new and improved spanning ratios for yao graphs":
    also connected through other hyperedges:
      - Hyperedge HE-6 (induced by source paper "truly optimal euclidean spanners")
  Member "an infinite class of sparse yao spanners":
    also connected through other hyperedges:
      - Hyperedge HE-7 (induced by source paper "truly optimal euclidean spanners")
  Member "π 2 angle yao graphs are spanners":
    also connected through other hyperedges:
      - Hyperedge HE-8 (induced by source paper "truly optimal euclidean spanners")

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)