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: "on fair division of indivisible items"
  Abstract: We consider the task of assigning indivisible goods to a set of agents in a fair manner. Our notion of fairness is Nash social welfare, i.e., the goal is to maximize the geometric mean of the utilities of the agents. Each good comes in multiple items or copies, and the utility of an agent diminishes as it receives more items of the same good. The utility of a bundle of items for an agent is the sum of the utilities of the items in the bundle. Each agent has a utility cap beyond which he does not value additional items. We give a polynomial time approximation algorithm that maximizes Nash social welfare up to a factor of $e^{1/e} \approx 1.445$.

Connected through hyperedge HE-1 (induced by source paper "efx exists for three agents"):
  with members:
    - "envy freeness up to any item with high nash welfare the virtue of donating items"
    - "approximating nash social welfare under submodular valuations through un matchings"
    - "a little charity guarantees almost envy freeness"
    - "an improved approximation algorithm for maximin shares"
    - "almost envy freeness with general valuations"
    - "approximating the nash social welfare with budget additive valuations"
    - "finding fair and efficient allocations"
    - "convex program duality fisher markets and nash social welfare"

Connected through hyperedge HE-2 (induced by source paper "envy freeness up to any item with high nash welfare the virtue of donating items"):
  with members:
    - "comparing approximate relaxations of envy freeness"
    - "approximation algorithms for computing maximin share allocations"
    - "almost envy freeness with general valuations"
    - "approximating the nash social welfare with budget additive valuations"
    - "finding fair and efficient allocations"
    - "a discrete and bounded envy free cake cutting protocol for any number of agents"
    - "convex program duality fisher markets and nash social welfare"
    - "nash social welfare for indivisible items under separable piecewise linear concave utilities"

Connected through hyperedge HE-3 (induced by source paper "approximating nash social welfare under submodular valuations through un matchings"):
  with members:
    - "a tale of santa claus hypergraphs and matroids"
    - "approximating the nash social welfare with budget additive valuations"
    - "finding fair and efficient allocations"
    - "convex program duality fisher markets and nash social welfare"
    - "nash social welfare for indivisible items under separable piecewise linear concave utilities"
    - "nash social welfare matrix permanent and stable polynomials"
    - "apx hardness of maximizing nash social welfare with indivisible items"
    - "combinatorial algorithm for restricted max min fair allocation"

Connected through hyperedge HE-4 (induced by source paper "a little charity guarantees almost envy freeness"):
  with members:
    - "envy freeness up to any item with high nash welfare the virtue of donating items"
    - "an improved approximation algorithm for maximin shares"
    - "almost envy free allocations with connected bundles"
    - "groupwise maximin fair allocation of indivisible goods"
    - "almost envy freeness with general valuations"
    - "approximating the nash social welfare with budget additive valuations"
    - "finding fair and efficient allocations"
    - "convex program duality fisher markets and nash social welfare"

Connected through hyperedge HE-5 (induced by source paper "auction algorithms for market equilibrium with weak gross substitute demands"):
  with members:
    - "finding fair and efficient allocations"
    - "convex program duality fisher markets and nash social welfare"
    - "nash social welfare for indivisible items under separable piecewise linear concave utilities"
    - "nash social welfare matrix permanent and stable polynomials"
    - "ascending price algorithms for unknown markets"
    - "convergence of tâtonnement in fisher markets"
    - "tatonnement in ongoing markets of complementary goods"
    - "a combinatorial polynomial algorithm for the linear arrow debreu market"

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)