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: "the two edge connectivity survivable network design problem in planar graphs"
  Abstract: Consider the following problem: given a graph with edge costs and a subset Q of vertices, find a minimum-cost subgraph in which there are two edge-disjoint paths connecting every pair of vertices in Q. The problem is a failure-resilient analog of the Steiner tree problem arising, for example, in telecommunications applications. We study a more general mixed-connectivity formulation, also employed in telecommunications optimization. Given a number (or requirement) r(v) in {0, 1, 2} for each vertex v in the graph, find a minimum-cost subgraph in which there are min{r(u), r(v)} edge-disjoint u-to-v paths for every pair u, v of vertices. #R##N#We address the problem in planar graphs, considering a popular relaxation in which the solution is allowed to use multiple copies of the input-graph edges (paying separately for each copy). The problem is max SNP-hard in general graphs and strongly NP-hard in planar graphs. We give the first polynomial-time approximation scheme in planar graphs. The running time is O(n log n). #R##N#Under the additional restriction that the requirements are only non-zero for vertices on the boundary of a single face of a planar graph, we give a polynomial-time algorithm to find the optimal solution.

Connected through hyperedge HE-1 (induced by source paper "a ptas for subset tsp in minor free graphs"):
  with members:
    - "truly optimal euclidean spanners"
    - "greedy spanners are optimal in doubling metrics"
    - "on subexponential parameterized algorithms for steiner tree and directed subset tsp on planar graphs"
    - "minor free graphs have light spanners"
    - "the greedy spanner is existentially optimal"
    - "linear size distance preservers"
    - "graph minors for preserving terminal distances approximately lower and upper bounds"
    - "a light metric spanner"

Connected through hyperedge HE-2 (induced by source paper "on subexponential parameterized algorithms for steiner tree and directed subset tsp on planar graphs"):
  with members:
    - "slightly superexponential parameterized problems"
    - "subexponential parameterized algorithms for planar and apex minor free graphs via low treewidth pattern covering"
    - "on problems as hard as cnf sat"
    - "optimal parameterized algorithms for planar facility location problems using voronoi diagrams"
    - "a polynomial time bicriteria approximation scheme for planar bisection"
    - "network sparsification for steiner problems on planar and bounded genus graphs"
    - "known algorithms for edge clique cover are probably optimal"
    - "an efficient polynomial time approximation scheme for steiner forest in planar graphs"

Connected through hyperedge HE-3 (induced by source paper "linear time approximation schemes for planar minimum three edge connected and three vertex connected spanning subgraphs"):
  with members:
    - "approximation schemes for steiner forest on planar graphs and graphs of bounded treewidth"

Connected through hyperedge HE-4 (induced by source paper "a ptas for three edge connectivity in planar graphs"):
  with members:
    - "approximation schemes for steiner forest on planar graphs and graphs of bounded treewidth"

Connected through hyperedge HE-5 (induced by source paper "polynomial time approximation schemes for subset connectivity problems in bounded genus graphs"):
  with members:
    - "approximation schemes for steiner forest on planar graphs and graphs of bounded treewidth"
    - "dynamic generators of topologically embedded graphs"

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)