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 k column sparse packing programs"
  Abstract: We consider the class of packing integer programs (PIPs) that are column sparse, i.e. there is a specified upper bound k on the number of constraints that each variable appears in. We give an (ek+o(k))-approximation algorithm for k-column sparse PIPs, improving on recent results of $k^2\cdot 2^k$ and $O(k^2)$. We also show that the integrality gap of our linear programming relaxation is at least 2k-1; it is known that k-column sparse PIPs are $\Omega(k/ \log k)$-hard to approximate. We also extend our result (at the loss of a small constant factor) to the more general case of maximizing a submodular objective over k-column sparse packing constraints.

Connected through hyperedge HE-1 (induced by source paper "random order contention resolution schemes"):
  with members:
    - "optimal online contention resolution schemes via ex ante prophet inequalities"
    - "algorithms to approximate column sparse packing problems"
    - "online contention resolution schemes"
    - "submodular stochastic probing on matroids"
    - "a stochastic probing problem with applications"
    - "matroid prophet inequalities"
    - "when lp is the cure for your matching woes improved bounds for stochastic matchings"

Connected through hyperedge HE-2 (induced by source paper "toward optimal coupon allocation in social networks an approximate submodular optimization approach"):
  with members:
    - "scalable bicriteria algorithms for the threshold activation problem in online social networks"
    - "sketch based influence maximization and computation scaling up with guarantees"

Connected through hyperedge HE-3 (induced by source paper "bayesian budget feasibility with posted pricing"):
  with members:
    - "incentivizing high quality crowdwork"
    - "mechanism design for crowdsourcing an optimal 1 1 e competitive budget feasible mechanism for large markets"
    - "social status and badge design"
    - "budget feasible mechanism design from prior free to bayesian"
    - "prior free auctions for budgeted agents"
    - "bayesian combinatorial auctions expanding single buyer mechanisms to many buyers"
    - "optimal crowdsourcing contests"
    - "mechanism design via correlation gap"

Connected through hyperedge HE-4 (induced by source paper "algorithms as mechanisms the price of anarchy of relax and round"):
  with members:
    - "a unifying hierarchy of valuations with complements and substitutes"
    - "on the efficiency of the walrasian mechanism"
    - "valuation compressions in vcg based combinatorial auctions"
    - "multi parameter mechanisms with implicit payment computation"
    - "composable and efficient mechanisms"
    - "simultaneous auctions are almost efficient"
    - "from convex optimization to randomized mechanisms toward optimal combinatorial auctions"
    - "truthful mechanisms with implicit payment computation"

Connected through hyperedge HE-5 (induced by source paper "generalized hypergraph matching via iterated packing and local ratio"):
  with members:
    - "iterative packing for demand and hypergraph matching"

Connected through hyperedge HE-6 (induced by source paper "a stochastic probing problem with applications"):
  with members:
    - "matroid prophet inequalities"
    - "mechanism design via correlation gap"
    - "when lp is the cure for your matching woes improved bounds for stochastic matchings"
    - "budget constrained auctions with heterogeneous items"

Connected through hyperedge HE-7 (induced by source paper "approximating sparse covering integer programs online"):
  with members:
    - "on column restricted and priority covering integer programs"
    - "approximability of sparse integer programs"
    - "approximation algorithms for covering packing integer programs"
    - "the k server dual and loose competitiveness for paging"

Connected through hyperedge HE-8 (induced by source paper "precoder design for physical layer multicasting"):
  with members:
    - "efficient submodular function maximization under linear packing constraints"
    - "approximation analysis of influence spread in social networks"
    - "ranking with submodular valuations"

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)