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: "the stretch factor of the delaunay triangulation is less than 1 998"
  Abstract: Let $S$ be a finite set of points in the Euclidean plane. Let $D$ be a Delaunay triangulation of $S$. The stretch factor (also known as dilation or spanning ratio) of $D$ is the maximum ratio, among all points $p$ and $q$ in $S$, of the shortest path distance from $p$ to $q$ in $D$ over the Euclidean distance $||pq||$. Proving a tight bound on the stretch factor of the Delaunay triangulation has been a long-standing open problem in computational geometry. In this paper we prove that the stretch factor of the Delaunay triangulation is less than $\rho = 1.998$, significantly improving the current best upper bound of 2.42 by Keil and Gutwin [``The Delaunay triangulation closely approximates the complete Euclidean graph,” in Proceedings of the 1st Workshop on Algorithms and Data Structures (WADS), 1989, pp. 47--56]. Our bound of 1.998 also improves the upper bound of the best stretch factor that can be achieved by a plane spanner of a Euclidean graph (the current best upper bound is 2). Our result has a direc...

Connected through hyperedge HE-1 (induced by source paper "drawing graphs as spanners"):
  with members:
    - "on plane constrained bounded degree spanners"
    - "optimal monotone drawings of trees"
    - "strongly monotone drawings of planar graphs"
    - "on planar greedy drawings of 3 connected planar graphs"
    - "on monotone drawings of trees"
    - "lower bounds on the dilation of plane spanners"
    - "recognition and complexity of point visibility graphs"
    - "on self approaching and increasing chord drawings of 3 connected planar graphs"

Connected through hyperedge HE-2 (induced by source paper "local routing in sparse and lightweight geometric graphs"):
  with members:
    - "gabriel triangulations and angle monotone graphs local routing and recognition"
    - "optimal local routing on delaunay triangulations defined by empty equilateral triangles"

Connected through hyperedge HE-3 (induced by source paper "linear size planar manhattan network for convex point sets"):
  with members:
    - "geometric biplane graphs ii graph augmentation"

Connected through hyperedge HE-4 (induced by source paper "a bounding box overlay for competitive routing in hybrid communication networks"):
  with members:
    - "competitive routing in hybrid communication networks"

Connected through hyperedge HE-5 (induced by source paper "dushnik miller dimension of td delaunay complexes"):
  with members:
    - "degree four plane spanners simpler and better"

Connected through hyperedge HE-6 (induced by source paper "the stretch factor of hexagon delaunay triangulations"):
  with members:
    - "on the stretch factor of convex delaunay graphs"

Connected through hyperedge HE-7 (induced by source paper "competitive routing in hybrid communication networks"):
  with members:
    - "improved leader election for self organizing programmable matter"

Connected through hyperedge HE-8 (induced by source paper "gabriel triangulations and angle monotone graphs local routing and recognition"):
  with members:
    - "lower bounds on the dilation of plane spanners"
    - "optimal local routing on delaunay triangulations defined by empty equilateral triangles"
    - "increasing chord graphs on point sets"
    - "self approaching graphs"

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)