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: "approximate distance oracles with improved preprocessing time"
  Abstract: Given an undirected graph $G$ with $m$ edges, $n$ vertices, and non-negative edge weights, and given an integer $k\geq 1$, we show that for some universal constant $c$, a $(2k-1)$-approximate distance oracle for $G$ of size $O(kn^{1 + 1/k})$ can be constructed in $O(\sqrt km + kn^{1 + c/\sqrt k})$ time and can answer queries in $O(k)$ time. We also give an oracle which is faster for smaller $k$. Our results break the quadratic preprocessing time bound of Baswana and Kavitha for all $k\geq 6$ and improve the $O(kmn^{1/k})$ time bound of Thorup and Zwick except for very sparse graphs and small $k$. When $m = \Omega(n^{1 + c/\sqrt k})$ and $k = O(1)$, our oracle is optimal w.r.t.\ both stretch, size, preprocessing time, and query time, assuming a widely believed girth conjecture by Erd\H{o}s.

Connected through hyperedge HE-1 (induced by source paper "faster approximation algorithms for computing shortest cycles on weighted graphs"):
  with members:
    - "towards tight approximation bounds for graph diameter and eccentricities"
    - "fully polynomial fpt algorithms for some classes of bounded clique width graphs"
    - "new subquadratic approximation algorithms for the girth"
    - "tight hardness for shortest cycles and paths in sparse graphs"
    - "on the power of tree depth for fully polynomial fpt algorithms"
    - "approximating cycles in directed graphs fast algorithms for girth and roundtrip spanners"
    - "subtree isomorphism revisited"
    - "polynomial fixed parameter algorithms a case study for longest path on interval graphs"

Connected through hyperedge HE-2 (induced by source paper "pruning based distance sketches with provable guarantees on random graphs"):
  with members:
    - "an axiomatic and an average case analysis of algorithms and heuristics for metric properties of graphs"
    - "algorithmic and hardness results for the hub labeling problem"
    - "on the complexity of hub labeling"
    - "sublinear distance labeling for sparse graphs"
    - "route planning in transportation networks"
    - "hop doubling label indexing for point to point distance querying on scale free networks"
    - "a scalable generative graph model with community structure"
    - "separating hierarchical and general hub labelings"

Connected through hyperedge HE-3 (induced by source paper "fast and compact exact distance oracle for planar graphs"):
  with members:
    - "voronoi diagrams on planar graphs and computing the diameter in deterministic tilde o n 5 3 time"
    - "subquadratic algorithms for the diameter and the sum of pairwise distances in planar graphs"
    - "improved bounds for shortest paths in dense distance graphs"
    - "popular conjectures as a barrier for dynamic planar graph algorithms"
    - "approximate distance oracles for planar graphs with improved query time space tradeoff"
    - "structured recursive separator decompositions for planar graphs in linear time"
    - "linear space approximate distance oracles for planar bounded genus and minor free graphs"
    - "improved distance queries in planar graphs"

Connected through hyperedge HE-4 (induced by source paper "distance labelings on random power law graphs"):
  with members:
    - "an axiomatic and an average case analysis of algorithms and heuristics for metric properties of graphs"
    - "algorithmic and hardness results for the hub labeling problem"
    - "on the complexity of hub labeling"
    - "fast exact shortest path distance queries on large networks by pruned landmark labeling"
    - "linear space approximate distance oracles for planar bounded genus and minor free graphs"

Connected through hyperedge HE-5 (induced by source paper "approximate distance oracles for planar graphs with improved query time space tradeoff"):
  with members:
    - "approximate distance oracle with constant query time"
    - "approximate distance oracles with improved query time"
    - "linear space approximate distance oracles for planar bounded genus and minor free graphs"
    - "exact distance oracles for planar graphs"
    - "ramsey partitions and proximity data structures"

Connected through hyperedge HE-6 (induced by source paper "a linear size logarithmic stretch path reporting distance oracle for general graphs"):
  with members:
    - "space efficient path reporting approximate distance oracles"
    - "approximate distance oracle with constant query time"
    - "faster approximate distance queries and compact routing in sparse graphs"
    - "ramsey partitions and proximity data structures"
    - "lower stretch spanning trees"

Connected through hyperedge HE-7 (induced by source paper "hierarchical oracles for time dependent networks"):
  with members:
    - "route planning in transportation networks"
    - "distance oracles for time dependent networks"
    - "approximate distance oracles with improved query time"
    - "fast precise and dynamic distance queries"

Connected through hyperedge HE-8 (induced by source paper "engineering oracles for time dependent road networks"):
  with members:
    - "hierarchical oracles for time dependent networks"
    - "route planning in transportation networks"
    - "distance oracles for time dependent networks"
    - "approximate distance oracles with improved query time"

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.DM(Discrete Mathematics)