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: "on collinear sets in straight line drawings"
  Abstract: We consider straight line drawings of a planar graph $G$ with possible edge crossings. The \emph{untangling problem} is to eliminate all edge crossings by moving as few vertices as possible to new positions. Let $fix(G)$ denote the maximum number of vertices that can be left fixed in the worst case. In the \emph{allocation problem}, we are given a planar graph $G$ on $n$ vertices together with an $n$-point set $X$ in the plane and have to draw $G$ without edge crossings so that as many vertices as possible are located in $X$. Let $fit(G)$ denote the maximum number of points fitting this purpose in the worst case. As $fix(G)\le fit(G)$, we are interested in upper bounds for the latter and lower bounds for the former parameter. #R##N#For each $\epsilon>0$, we construct an infinite sequence of graphs with $fit(G)=O(n^{\sigma+\epsilon})$, where $\sigma<0.99$ is a known graph-theoretic constant, namely the shortness exponent for the class of cubic polyhedral graphs. To the best of our knowledge, this is the first example of graphs with $fit(G)=o(n)$. On the other hand, we prove that $fix(G)\ge\sqrt{n/30}$ for all $G$ with tree-width at most 2. This extends the lower bound obtained by Goaoc et al. [Discrete and Computational Geometry 42:542-569 (2009)] for outerplanar graphs. #R##N#Our upper bound for $fit(G)$ is based on the fact that the constructed graphs can have only few collinear vertices in any crossing-free drawing. To prove the lower bound for $fix(G)$, we show that graphs of tree-width 2 admit drawings that have large sets of collinear vertices with some additional special properties.

Connected through hyperedge HE-1 (induced by source paper "cubic planar graphs that cannot be drawn on few lines"):
  with members:
    - "line and plane cover numbers revisited"
    - "the complexity of drawing graphs on few lines and few planes"
    - "drawing graphs on few lines and few planes"

Connected through hyperedge HE-2 (induced by source paper "aligned drawings of planar graphs"):
  with members:
    - "the complexity of drawing graphs on few lines and few planes"
    - "drawing planar graphs with many collinear vertices"
    - "drawing graphs on few lines and few planes"
    - "the utility of untangling"
    - "abusing the tutte matrix an algebraic instance compression for the k set cycle problem"
    - "a center transversal theorem for hyperplanes and applications to graph drawing"

Connected through hyperedge HE-3 (induced by source paper "drawing planar graphs with many collinear vertices"):
  with members:
    - "the utility of untangling"
    - "a note on planar partial 3 trees"
    - "untangling planar graphs from a specified vertex position hard cases"
    - "untangling polygons and graphs"
    - "untangling a planar graph"
    - "a polynomial bound for untangling geometric planar graphs"

Connected through hyperedge HE-4 (induced by source paper "drawing graphs on few lines and few planes"):
  with members:
    - "the complexity of drawing graphs on few lines and few planes"
    - "graph layouts via layered separators"
    - "layout of graphs with bounded tree width"

Connected through hyperedge HE-5 (induced by source paper "the utility of untangling"):
  with members:
    - "superpatterns and universal point sets"
    - "sefe with no mapping via large induced outerplane graphs in plane graphs"
    - "how many vertex locations can be arbitrarily chosen when drawing planar graphs"
    - "on universal point sets for planar graphs"
    - "simultaneous embedding of planar graphs"
    - "untangling planar graphs from a specified vertex position hard cases"
    - "untangling polygons and graphs"
    - "on a tree and a path with no geometric simultaneous embedding"

Connected through hyperedge HE-6 (induced by source paper "untangling planar graphs from a specified vertex position hard cases"):
  with members:
    - "untangling polygons and graphs"
    - "untangling a planar graph"
    - "a polynomial bound for untangling geometric planar graphs"
    - "on the obfuscation complexity of planar graphs"
    - "moving vertices to make drawings plane"

Connected through hyperedge HE-7 (induced by source paper "untangling polygons and graphs"):
  with members:
    - "untangling a planar graph"
    - "a polynomial bound for untangling geometric planar graphs"
    - "on the obfuscation complexity of planar graphs"
    - "moving vertices to make drawings plane"

Connected through hyperedge HE-8 (induced by source paper "a polynomial bound for untangling geometric planar graphs"):
  with members:
    - "untangling polygons and graphs"
    - "on the obfuscation complexity of planar graphs"
    - "moving vertices to make drawings plane"

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)