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: "calculating the unrooted subtree prune and regraft distance"
  Abstract: The subtree prune-and-regraft (SPR) distance metric is a fundamental way of comparing evolutionary trees. It has wide-ranging applications, such as to study lateral genetic transfer, viral recombination, and Markov chain Monte Carlo phylogenetic inference. Although the rooted version of SPR distance can be computed relatively efficiently between rooted trees using fixed-parameter-tractable maximum agreement forest (MAF) algorithms, no MAF formulation is known for the unrooted case. Correspondingly, previous algorithms are unable to compute unrooted SPR distances larger than 7. #R##N#In this paper, we substantially advance understanding of and computational algorithms for the unrooted SPR distance. First we identify four properties of optimal SPR paths, each of which suggests that no MAF formulation exists in the unrooted case. Then we introduce the replug distance, a new lower bound on the unrooted SPR distance that is amenable to MAF methods, and give an efficient fixed-parameter algorithm for calculating it. Finally, we develop a "progressive A*" search algorithm using multiple heuristics, including the TBR and replug distances, to exactly compute the unrooted SPR distance. Our algorithm is nearly two orders of magnitude faster than previous methods on small trees, and allows computation of unrooted SPR distances as large as 14 on trees with 50 leaves.

Connected through hyperedge HE-1 (induced by source paper "an analysis of the geodesic distance and other comparative metrics for tree like structures"):
  with members:
    - "hybridization number on three trees"
    - "hybridization number on three rooted binary trees is ept"
    - "an almost linear time algorithm for approximate max flow in undirected graphs and its multicommodity generalizations"
    - "nearly maximum flows in nearly linear time"
    - "solving the maximum agreement subtree and the maximum compatible tree problems on many bounded degree trees"

Connected through hyperedge HE-2 (induced by source paper "a tight kernel for computing the tree bisection and reconnection distance between two phylogenetic trees"):
  with members:
    - "on unrooted and root uncertain variants of several well known phylogenetic network problems"
    - "hybridization number on three rooted binary trees is ept"
    - "kernelizations for the hybridization number problem on multiple nonbinary trees"
    - "kernelization lower bounds by cross composition"
    - "constructing minimal phylogenetic networks from softwired clusters is fixed parameter tractable"

Connected through hyperedge HE-3 (induced by source paper "a synopsis of comparative metrics for classifications"):
  with members:
    - "hybridization number on three trees"
    - "hybridization number on three rooted binary trees is ept"
    - "solving the maximum agreement subtree and the maximum compatible tree problems on many bounded degree trees"

Connected through hyperedge HE-4 (induced by source paper "treewidth distance on phylogenetic trees"):
  with members:
    - "on unrooted and root uncertain variants of several well known phylogenetic network problems"
    - "efficient fpt algorithms for strict compatibility of unrooted phylogenetic trees"
    - "kernelizations for the hybridization number problem on multiple nonbinary trees"
    - "a complete anytime algorithm for treewidth"
    - "graph triangulations and the compatibility of unrooted phylogenetic trees"

Connected through hyperedge HE-5 (induced by source paper "efficiently inferring pairwise subtree prune and regraft adjacencies between phylogenetic trees"):
  with members:
    - "ricci ollivier curvature of the rooted phylogenetic subtree prune regraft graph"

Connected through hyperedge HE-6 (induced by source paper "ricci ollivier curvature of the rooted phylogenetic subtree prune regraft graph"):
  with members:
    - "efficiently inferring pairwise subtree prune and regraft adjacencies between phylogenetic trees"
    - "ricci curvature of the internet topology"

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.DS(Data Structures and Algorithms)