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: "approximating the nash social welfare with budget additive valuations"
  Abstract: We present the first constant-factor approximation algorithm for maximizing the Nash social welfare when allocating indivisible items to agents with budget-additive valuation functions. Budget-additive valuations represent an important class of submodular functions. They have attracted a lot of research interest in recent years due to many interesting applications. For every $\varepsilon > 0$, our algorithm obtains a $(2.404 + \varepsilon)$-approximation in time polynomial in the input size and $1/\varepsilon$. #R##N#Our algorithm relies on rounding an approximate equilibrium in a linear Fisher market where sellers have earning limits (upper bounds on the amount of money they want to earn) and buyers have utility limits (upper bounds on the amount of utility they want to achieve). In contrast to markets with either earning or utility limits, these markets have not been studied before. They turn out to have fundamentally different properties. #R##N#Although the existence of equilibria is not guaranteed, we show that the market instances arising from the Nash social welfare problem always have an equilibrium. Further, we show that the set of equilibria is not convex, answering a question of [Cole et al, EC 2017]. We design an FPTAS to compute an approximate equilibrium. We show that the problem of computing an exact equilibrium lies in the intersection of classes PLS (Polynomial Local Search) and PPAD (Polynomial Parity Algorithms on Directed Graphs). For a constant number of buyers or goods, we give a polynomial-time algorithm to compute an exact equilibrium.

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"
    - "on fair division of indivisible items"
    - "almost envy freeness with general 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"
    - "on fair division of indivisible items"
    - "approximation algorithms for computing maximin share allocations"
    - "almost envy freeness with general 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 "satiation in fisher markets and approximation of nash social welfare"):
  with members:
    - "near optimal online algorithms and fast approximation algorithms for resource allocation problems"
    - "a strongly polynomial algorithm for linear exchange markets"
    - "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"
    - "an improved combinatorial polynomial algorithm for the linear arrow debreu market"
    - "apx hardness of maximizing nash social welfare with indivisible items"

Connected through hyperedge HE-4 (induced by source paper "approximating nash social welfare under submodular valuations through un matchings"):
  with members:
    - "on fair division of indivisible items"
    - "a tale of santa claus hypergraphs and matroids"
    - "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-5 (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"
    - "on fair division of indivisible items"
    - "groupwise maximin fair allocation of indivisible goods"
    - "almost envy freeness with general valuations"
    - "finding fair and efficient allocations"
    - "convex program duality fisher markets and nash social welfare"

Connected through hyperedge HE-6 (induced by source paper "on the existence of pareto efficient and envy free allocations"):
  with members:
    - "near optimal communication lower bounds for approximate nash equilibria"
    - "communication complexity of cake cutting"
    - "almost envy freeness with general valuations"
    - "communication complexity of discrete fair division"
    - "convex program duality fisher markets and nash social welfare"
    - "computing equilibria in markets with budget additive utilities"
    - "nash social welfare for indivisible items under separable piecewise linear concave utilities"
    - "communication complexity of approximate nash equilibria"

Connected through hyperedge HE-7 (induced by source paper "fairness efficiency tradeoffs in dynamic fair division"):
  with members:
    - "a simple online fair division problem"
    - "a strongly polynomial algorithm for linear exchange markets"
    - "dynamic fair division problem with general valuations"
    - "when do envy free allocations exist"
    - "finding fair and efficient allocations"
    - "online fair division analysing a food bank problem"

Connected through hyperedge HE-8 (induced by source paper "greedy algorithms for maximizing nash social welfare"):
  with members:
    - "almost envy freeness with general 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"
    - "apx hardness of maximizing nash social welfare with indivisible items"
    - "combinatorial auctions with decreasing marginal utilities"

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)