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: "asymmetric traveling salesman path and directed latency problems"
  Abstract: We study integrality gaps and approximability of two closely related problems on directed graphs. Given a set V of n nodes in an underlying asymmetric metric and two specified nodes s and t, both problems ask to find an s-t path visiting all other nodes. In the asymmetric traveling salesman path problem (ATSPP), the objective is to minimize the total cost of this path. In the directed latency problem, the objective is to minimize the sum of distances on this path from s to each node. Both of these problems are NP-hard. The best known approximation algorithms for ATSPP had ratio O(log n) until the very recent result that improves it to O(log n/ log log n). However, only a bound of O(sqrt(n)) for the integrality gap of its linear programming relaxation has been known. For directed latency, the best previously known approximation algorithm has a guarantee of O(n^(1/2+eps)), for any constant eps > 0. We present a new algorithm for the ATSPP problem that has an approximation ratio of O(log n), but whose analysis also bounds the integrality gap of the standard LP relaxation of ATSPP by the same factor. This solves an open problem posed by Chekuri and Pal [2007]. We then pursue a deeper study of this linear program and its variations, which leads to an algorithm for the k-person ATSPP (where k s-t paths of minimum total length are sought) and an O(log n)-approximation for the directed latency problem.

Connected through hyperedge HE-1 (induced by source paper "a constant factor approximation for directed latency in quasi polynomial time"):
  with members:
    - "the asymmetric traveling salesman path lp has constant integrality ratio"
    - "a constant factor approximation algorithm for the asymmetric traveling salesman problem"
    - "compact provably good lps for orienteering and regret bounded vehicle routing"
    - "an improved integrality gap for asymmetric tsp paths"
    - "approximation algorithms for regret bounded vehicle routing and applications to distance constrained vehicle routing"
    - "improving christofides algorithm for the s t path tsp"

Connected through hyperedge HE-2 (induced by source paper "the asymmetric traveling salesman path lp has constant integrality ratio"):
  with members:
    - "a constant factor approximation algorithm for the asymmetric traveling salesman problem"
    - "approximating atsp by relaxing connectivity"
    - "an improved integrality gap for asymmetric tsp paths"

Connected through hyperedge HE-3 (induced by source paper "an improved integrality gap for asymmetric tsp paths"):
  with members:
    - "eight fifth approximation for the path tsp"
    - "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"
    - "improving christofides algorithm for the s t path tsp"
    - "the asymmetric traveling salesman problem on graphs with bounded genus"

Connected through hyperedge HE-4 (induced by source paper "approximation algorithms for regret bounded vehicle routing and applications to distance constrained vehicle routing"):
  with members:
    - "approximating bin packing within o log opt log log opt bins"
    - "multiple traveling salesmen in asymmetric metrics"
    - "santa claus schedules jobs on unrelated machines"
    - "facility location with client latencies linear programming based techniques for minimum latency problems"

Connected through hyperedge HE-5 (induced by source paper "lift and project integrality gaps for the traveling salesperson problem"):
  with members:
    - "eight fifth approximation for the path tsp"
    - "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"
    - "improved inapproximability for tsp"
    - "improving christofides algorithm for the s t path tsp"
    - "approximating graphic tsp by matchings"
    - "lp based approximation algorithms for traveling salesman path problems"
    - "13 9 approximation for graphic tsp"
    - "the asymmetric traveling salesman problem on graphs with bounded genus"

Connected through hyperedge HE-6 (induced by source paper "multiple traveling salesmen in asymmetric metrics"):
  with members:
    - "eight fifth approximation for the path tsp"
    - "an improved integrality gap for asymmetric tsp paths"
    - "new inapproximability bounds for tsp"
    - "improving christofides algorithm for the s t path tsp"
    - "facility location with client latencies linear programming based techniques for minimum latency problems"

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)