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: "an o 1 approximation for minimum spanning tree interdiction"
  Abstract: Network interdiction problems are a natural way to study the sensitivity of a network optimization problem with respect to the removal of a limited set of edges or vertices. One of the oldest and best-studied interdiction problems is minimum spanning tree (MST) interdiction. Here, an undirected multigraph with nonnegative edge weights and positive interdiction costs on its edges is given, together with a positive budget B. The goal is to find a subset of edges R, whose total interdiction cost does not exceed B, such that removing R leads to a graph where the weight of an MST is as large as possible. Frederickson and Solis-Oba (SODA 1996) presented an O(log m)-approximation for MST interdiction, where m is the number of edges. Since then, no further progress has been made regarding approximations, and the question whether MST interdiction admits an O(1)-approximation remained open. #R##N#We answer this question in the affirmative, by presenting a 14-approximation that overcomes two main hurdles that hindered further progress so far. Moreover, based on a well-known 2-approximation for the metric traveling salesman problem (TSP), we show that our O(1)-approximation for MST interdiction implies an O(1)-approximation for a natural interdiction version of metric TSP.

Connected through hyperedge HE-1 (induced by source paper "downgrading to minimize connectivity"):
  with members:
    - "improved algorithms for mst and metric tsp interdiction"
    - "hardness and approximation for network flow interdiction"
    - "simple and fast rounding algorithms for directed and node weighted multiway cut"
    - "improved region growing and combinatorial algorithms for k route cut problems"
    - "multiway cut pairwise realizable distributions and descending thresholds"
    - "approximation algorithms and hardness of the k route cut problem"

Connected through hyperedge HE-2 (induced by source paper "improved algorithms for mst and metric tsp interdiction"):
  with members:
    - "improved region growing and combinatorial algorithms for k route cut problems"
    - "reducing the rank of a matroid"

Connected through hyperedge HE-3 (induced by source paper "blocking self avoiding walks stops cyber epidemics a scalable gpu based approach"):
  with members:
    - "stop and stare optimal sampling algorithms for viral marketing in billion scale networks"

Connected through hyperedge HE-4 (induced by source paper "hardness and approximation for network flow interdiction"):
  with members:
    - "reducing the rank of a matroid"
    - "polynomial integrality gaps for strong sdp relaxations of densest k subgraph"
    - "approximation algorithms and hardness of the k route cut problem"

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)