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: "finding topological subgraphs is fixed parameter tractable"
  Abstract: We show that for every fixed undirected graph $H$, there is a $O(|V(G)|^3)$ time algorithm that tests, given a graph $G$, if $G$ contains $H$ as a topological subgraph (that is, a subdivision of $H$ is subgraph of $G$). This shows that topological subgraph testing is fixed-parameter tractable, resolving a longstanding open question of Downey and Fellows from 1992. As a corollary, for every $H$ we obtain an $O(|V(G)|^3)$ time algorithm that tests if there is an immersion of $H$ into a given graph $G$. This answers another open question raised by Downey and Fellows in 1992.

Connected through hyperedge HE-1 (induced by source paper "hitting topological minors is fpt"):
  with members:
    - "hitting topological minor models in planar graphs is fixed parameter tractable"
    - "improved analysis of highest degree branching for feedback vertex set"
    - "losing treewidth by separating subsets"
    - "a 2 approximation algorithm for feedback vertex set in tournaments"
    - "polylogarithmic approximation for minimum planarization almost"
    - "exact algorithms for maximum independent set"
    - "bidimensionality and kernels"
    - "exact algorithms via monotone local search"

Connected through hyperedge HE-2 (induced by source paper "binary constraint satisfaction problems defined by excluded topological minors"):
  with members:
    - "a dichotomy theorem for nonuniform csps"
    - "the proof of csp dichotomy conjecture"
    - "the power of arc consistency for csps defined by partially ordered forbidden patterns"
    - "variable and value elimination in binary constraint satisfaction via forbidden patterns"
    - "the tractability of csp classes defined by forbidden patterns"
    - "hybrid tractability of valued constraint problems"
    - "tractable hypergraph properties for constraint satisfaction and conjunctive queries"

Connected through hyperedge HE-3 (induced by source paper "parametrised algorithms for directed modular width"):
  with members:
    - "on directed feedback vertex set parameterized by treewidth"
    - "an algorithmic metatheorem for directed treewidth"
    - "the directed grid theorem"
    - "parameterized algorithms for modular width"
    - "the planar directed k vertex disjoint paths problem is fixed parameter tractable"
    - "finding an induced subdivision of a digraph"

Connected through hyperedge HE-4 (induced by source paper "hitting topological minor models in planar graphs is fixed parameter tractable"):
  with members:
    - "the planar directed k vertex disjoint paths problem is fixed parameter tractable"
    - "obtaining planarity by contracting few edges"
    - "obtaining a planar graph by vertex deletion"

Connected through hyperedge HE-5 (induced by source paper "planar disjoint paths in linear time"):
  with members:
    - "a lower bound on the tree width of graphs with irrelevant vertices"
    - "obtaining a planar graph by vertex deletion"

Connected through hyperedge HE-6 (induced by source paper "an fpt 2 approximation for tree cut decomposition"):
  with members:
    - "constructive algorithm for path width of matroids"
    - "bidimensionality and eptas"

Connected through hyperedge HE-7 (induced by source paper "on the complexity of finding internally vertex disjoint long directed paths"):
  with members:
    - "finding two edge disjoint paths with length constraints"
    - "a randomized algorithm for long directed cycle"
    - "representative families a unified tradeoff based approach"
    - "kernelization lower bounds by cross composition"

Connected through hyperedge HE-8 (induced by source paper "parameterized algorithms for min max multiway cut and list digraph homomorphism"):
  with members:
    - "an fpt 2 approximation for tree cut decomposition"
    - "space complexity of list h colouring a dichotomy"
    - "list h coloring a graph by removing few vertices"
    - "minimum bisection is fixed parameter tractable"
    - "designing fpt algorithms for cut problems using randomized contractions"
    - "minimum k way cut of bounded size is fixed parameter tractable"
    - "finding small separators in linear time via treewidth reduction"
    - "fixed parameter tractability of directed multiway cut parameterized by the size of the cutset"

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)