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: "a polylogarithmic competitive algorithm for the k server problem"
  Abstract: We give the first polylogarithmic-competitive randomized online algorithm for the $k$-server problem on an arbitrary finite metric space. In particular, our algorithm achieves a competitive ratio of O(log^3 n log^2 k log log n) for any metric space on n points. Our algorithm improves upon the deterministic (2k-1)-competitive algorithm of Koutsoupias and Papadimitriou [J.ACM'95] whenever n is sub-exponential in k.

Connected through hyperedge HE-1 (induced by source paper "stochastic k server how should uber work"):
  with members:
    - "beating 1 frac 1 e for ordered prophets"
    - "adcell ad allocation in cellular networks"
    - "better algorithms for unfair metrical task systems and applications"
    - "truly online paging with locality of reference"
    - "competitive paging algorithms"

Connected through hyperedge HE-2 (induced by source paper "prioritized metric structures and embedding"):
  with members:
    - "a linear size logarithmic stretch path reporting distance oracle for general graphs"
    - "approximate distance oracle with constant query time"
    - "approximate distance oracles with improved query time"
    - "ramsey partitions and proximity data structures"
    - "embedding metrics into ultrametrics and graphs into spanning trees with constant average distortion"

Connected through hyperedge HE-3 (induced by source paper "serving online requests with mobile servers"):
  with members:
    - "local search based approximation algorithms for mobile facility location problems"
    - "an optimal bifactor approximation algorithm for the metric uncapacitated facility location problem"
    - "greedy facility location algorithms analyzed using dual fitting with factor revealing lp"

Connected through hyperedge HE-4 (induced by source paper "distributed multi depot routing without communications"):
  with members:
    - "shorter tours by nicer ears 7 5 approximation for graphic tsp 3 2 for the path version and 4 3 for two edge connected subgraphs"
    - "approximating graphic tsp by matchings"
    - "13 9 approximation for graphic tsp"

Connected through hyperedge HE-5 (induced by source paper "online covering with convex objectives and applications"):
  with members:
    - "online primal dual for non linear optimization with applications to speed scaling"

Connected through hyperedge HE-6 (induced by source paper "a competitive ratio approximation scheme for the k server problem in fixed finite metrics"):
  with members:
    - "competitive ratio approximation schemes for minimizing the makespan in the online list model"
    - "randomized online computation with high probability guarantees"
    - "a new approach to online scheduling approximating the optimal competitive ratio"
    - "ramsey type theorems for metric spaces with applications to online problems"
    - "better algorithms for unfair metrical task systems and applications"
    - "competitive paging algorithms"

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)