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: "structural parameters tight bounds and approximation for k r center"
  Abstract: In $(k,r)$-Center we are given a (possibly edge-weighted) graph and are asked to select at most $k$ vertices (centers), so that all other vertices are at distance at most $r$ from a center. In this paper we provide a number of tight fine-grained bounds on the complexity of this problem with respect to various standard graph parameters. Specifically: #R##N#- For any $r\ge 1$, we show an algorithm that solves the problem in $O^*((3r+1)^{\textrm{cw}})$ time, where $\textrm{cw}$ is the clique-width of the input graph, as well as a tight SETH lower bound matching this algorithm's performance. As a corollary, for $r=1$, this closes the gap that previously existed on the complexity of Dominating Set parameterized by $\textrm{cw}$. #R##N#- We strengthen previously known FPT lower bounds, by showing that $(k,r)$-Center is W[1]-hard parameterized by the input graph's vertex cover (if edge weights are allowed), or feedback vertex set, even if $k$ is an additional parameter. Our reductions imply tight ETH-based lower bounds. Finally, we devise an algorithm parameterized by vertex cover for unweighted graphs. #R##N#- We show that the complexity of the problem parameterized by tree-depth is $2^{\Theta(\textrm{td}^2)}$ by showing an algorithm of this complexity and a tight ETH-based lower bound. #R##N#We complement these mostly negative results by providing FPT approximation schemes parameterized by clique-width or treewidth which work efficiently independently of the values of $k,r$. In particular, we give algorithms which, for any $\epsilon>0$, run in time $O^*((\textrm{tw}/\epsilon)^{O(\textrm{tw})})$, $O^*((\textrm{cw}/\epsilon)^{O(\textrm{cw})})$ and return a $(k,(1+\epsilon)r)$-center, if a $(k,r)$-center exists, thus circumventing the problem's W-hardness.

Connected through hyperedge HE-1 (induced by source paper "regular intersection emptiness of graph problems finding a needle in a haystack of graphs with the help of automata"):
  with members:
    - "from decidability to undecidability by considering regular sets of instances"
    - "regular realizability problems and regular languages"
    - "regular realizability problems and models of a generalized nondeterminism"

Connected through hyperedge HE-2 (induced by source paper "travelling on graphs with small highway dimension"):
  with members:
    - "hierarchy of transportation network parameters and hardness results"
    - "the parameterized hardness of the k center problem in transportation networks"
    - "a 1 varepsilon embedding of low highway dimension graphs into bounded treewidth graphs"
    - "beyond highway dimension small distance labels using tree skeletons"
    - "solving generalized maximum weight connected subgraph problem for network enrichment analysis"
    - "fixed parameter approximations for k center problems in low highway dimension graphs"
    - "the traveling salesman problem low dimensionality implies a polynomial time approximation scheme"
    - "efficient activity detection in untrimmed video with max subgraph search"

Connected through hyperedge HE-3 (induced by source paper "new algorithms for mixed dominating set"):
  with members:
    - "parameterized orientable deletion"
    - "tight approximation ratio for minimum maximal matching"
    - "finer tight bounds for coloring on clique width"
    - "structurally parameterized d scattered set"
    - "an efficient algorithm for mixed domination on generalized series parallel graphs"
    - "fine grained parameterized complexity analysis of graph coloring problems"
    - "on fixed parameter tractability of the mixed domination problem for graphs with bounded tree width"
    - "optimal dynamic program for r domination problems over tree decompositions"

Connected through hyperedge HE-4 (induced by source paper "new results on directed edge dominating set"):
  with members:
    - "optimal dynamic program for r domination problems over tree decompositions"
    - "analytical approach to parallel repetition"
    - "directed nowhere dense classes of graphs"

Connected through hyperedge HE-5 (induced by source paper "the parameterized hardness of the k center problem in transportation networks"):
  with members:
    - "hierarchy of transportation network parameters and hardness results"
    - "a 1 varepsilon embedding of low highway dimension graphs into bounded treewidth graphs"
    - "polynomial time approximation schemes for k center and bounded capacity vehicle routing in metrics with bounded highway dimension"
    - "the limited blessing of low dimensionality when 1 1 d is the best possible exponent for d dimensional geometric problems"
    - "fixed parameter approximations for k center problems in low highway dimension graphs"
    - "optimal parameterized algorithms for planar facility location problems using voronoi diagrams"
    - "analytical approach to parallel repetition"
    - "improved approximation algorithms for budgeted node weighted steiner problems"

Connected through hyperedge HE-6 (induced by source paper "structurally parameterized d scattered set"):
  with members:
    - "parameterized power vertex cover"
    - "on distance d independent set and other problems in graphs with few minimal separators"
    - "optimal parameterized algorithms for planar facility location problems using voronoi diagrams"
    - "optimal dynamic program for r domination problems over tree decompositions"
    - "parameterized approximation schemes using graph widths"
    - "known algorithms on graphs of bounded treewidth are probably optimal"

Connected through hyperedge HE-7 (induced by source paper "parameterized approximation algorithms for some location problems in graphs"):
  with members:
    - "from gap eth to fpt inapproximability clique dominating set and more"
    - "fast approximation algorithms for p centres in large delta hyperbolic graphs"
    - "fixed parameter approximations for k center problems in low highway dimension graphs"
    - "optimal dynamic program for r domination problems over tree decompositions"

Connected through hyperedge HE-8 (induced by source paper "fixed parameter approximations for k center problems in low highway dimension graphs"):
  with members:
    - "the parameterized hardness of the k center problem in transportation networks"
    - "a 1 varepsilon embedding of low highway dimension graphs into bounded treewidth graphs"
    - "polynomial time approximation schemes for k center and bounded capacity vehicle routing in metrics with bounded highway dimension"
    - "beyond highway dimension small distance labels using tree skeletons"
    - "optimal parameterized algorithms for planar facility location problems using voronoi diagrams"
    - "parameterized approximation schemes using graph widths"

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.CC(Computational Complexity)