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: "tight algorithms for vertex cover with hard capacities on multigraphs and hypergraphs"
  Abstract: In this paper we give a f-approximation algorithm for the minimum unweighted Vertex Cover problem with Hard Capacity constraints (VCHC) on f-hypergraphs. This problem generalizes standard vertex cover for which the best known approximation ratio is also f and cannot be improved assuming the unique game conjecture. Our result is therefore essentially the best possible. This improves over the previous 2.155 (for f=2) and 2f-approximation algorithms by Cheung, Goemans and Wong (CGW). #R##N#At the heart of our approach is to apply iterative rounding to the problem with ideas coming from several previous works. We also give a faster implementation of the method based on certain iteratively rounding the solution to certain CGW-style covering LPs. #R##N#We note that independent of this work, Kao [#kao2017iterative] also recently obtained the same result.

Connected through hyperedge HE-1 (induced by source paper "a constant factor approximation for capacitated min max tree cover"):
  with members:
    - "a ptas for bounded capacity vehicle routing in planar graphs"
    - "a ptas for minimum makespan vehicle routing in trees"
    - "iterative partial rounding for vertex cover with hard capacities"
    - "an approximation algorithm for uniform capacitated k median problem with 1 epsilon capacity violation"
    - "a new approximation technique for resource allocation problems"

Connected through hyperedge HE-2 (induced by source paper "capacitated covering problems in geometric spaces"):
  with members:
    - "replica placement on bounded treewidth graphs"
    - "iterative partial rounding for vertex cover with hard capacities"
    - "capacitated dominating set on planar graphs"
    - "on uniform capacitated k median beyond the natural lp relaxation"
    - "lp based algorithms for capacitated facility location"
    - "analytical approach to parallel repetition"
    - "lp rounding for k centers with non uniform hard capacities"
    - "improved approximation algorithms for geometric set cover"

Connected through hyperedge HE-3 (induced by source paper "o f bi approximation for capacitated covering with hard capacities"):
  with members:
    - "iterative partial rounding for vertex cover with hard capacities"

Connected through hyperedge HE-4 (induced by source paper "iterative partial rounding for vertex cover with hard capacities"):
  with members:
    - "on uniform capacitated k median beyond the natural lp relaxation"

Connected through hyperedge HE-5 (induced by source paper "an improved approximation for k median and positive correlation in budgeted optimization"):
  with members:
    - "pipage rounding pessimistic estimators and matrix concentration"
    - "approximating k median via pseudo approximation"
    - "a systematic approach to bound factor revealing lps and its application to the metric and squared metric facility location problems"
    - "when lp is the cure for your matching woes improved bounds for stochastic matchings"
    - "greedy facility location algorithms analyzed using dual fitting with factor revealing lp"

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)