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 traveling salesman problem on cubic and subcubic graphs"
  Abstract: We study the Travelling Salesman Problem (TSP) on the metric completion of cubic and subcubic graphs, which is known to be NP-hard. The problem is of interest because of its relation to the famous 4/3 conjecture for metric TSP, which says that the integrality gap, i.e., the worst case ratio between the optimal values of the TSP and its linear programming relaxation (the subtour elimination relaxation), is 4/3. We present the first algorithm for cubic graphs with approximation ratio 4/3. The proof uses polyhedral techniques in a surprising way, which is of independent interest. In fact we prove constructively that for any cubic graph on $n$ vertices a tour of length 4n/3-2 exists, which also implies the 4/3 conjecture, as an upper bound, for this class of graph-TSP. #R##N#Recently, M\"omke and Svensson presented a randomized algorithm that gives a 1.461-approximation for graph-TSP on general graphs and as a side result a 4/3-approximation algorithm for this problem on subcubic graphs, also settling the 4/3 conjecture for this class of graph-TSP. We will present a way to derandomize their algorithm which leads to a smaller running time than the obvious derandomization. All of the latter also works for multi-graphs.

Connected through hyperedge HE-1 (induced by source paper "simple cubic graphs with no short traveling salesman tour"):
  with members:
    - "graphic tsp in cubic graphs"
    - "cubic tsp a 1 3 approximation"
    - "tsp tours in cubic graphs beyond 4 3"
    - "approximating graphic tsp by matchings"

Connected through hyperedge HE-2 (induced by source paper "shorter tours and longer detours uniform covers and a bit beyond"):
  with members:
    - "coloring down 3 2 approximation for special cases of the weighted tree augmentation problem"
    - "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"
    - "13 9 approximation for graphic tsp"

Connected through hyperedge HE-3 (induced by source paper "graphic tsp in cubic graphs"):
  with members:
    - "approximation hardness of graphic tsp on cubic graphs"
    - "new inapproximability bounds for tsp"
    - "improved inapproximability for tsp"
    - "approximating graphic tsp by matchings"
    - "13 9 approximation for graphic tsp"

Connected through hyperedge HE-4 (induced by source paper "cubic tsp a 1 3 approximation"):
  with members:
    - "graphic tsp in cubic graphs"
    - "a 9 7 approximation algorithm for graphic tsp in cubic bipartite graphs"

Connected through hyperedge HE-5 (induced by source paper "an improved analysis of the m omke svensson algorithm for graph tsp on subquartic graphs"):
  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"
    - "improving christofides algorithm for the s t path tsp"
    - "approximating graphic tsp by matchings"
    - "13 9 approximation for graphic tsp"

Connected through hyperedge HE-6 (induced by source paper "a 9 7 approximation algorithm for graphic tsp in cubic bipartite graphs"):
  with members:
    - "improved approximations for cubic and cubic bipartite tsp"
    - "an improved analysis of the m omke svensson algorithm for graph tsp on subquartic graphs"
    - "tsp tours in cubic graphs beyond 4 3"
    - "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"
    - "a 4 3 approximation for tsp on cubic 3 edge connected graphs"

Connected through hyperedge HE-7 (induced by source paper "approximation hardness of graphic tsp on cubic graphs"):
  with members:
    - "tsp tours in cubic graphs beyond 4 3"
    - "new inapproximability bounds for tsp"
    - "on approximation lower bounds for tsp with bounded metrics"
    - "approximating graphic tsp by matchings"
    - "13 9 approximation for graphic tsp"

Connected through hyperedge HE-8 (induced by source paper "on the integrality gap of the subtour lp for the 1 2 tsp"):
  with members:
    - "improved integrality gap upper bounds for tsp with distances one and two"
    - "practical graph isomorphism ii"
    - "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"
    - "a 4 3 approximation for tsp on cubic 3 edge connected graphs"
    - "a proof of the boyd carr conjecture"
    - "13 9 approximation for graphic tsp"

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)