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: "multistage knapsack"
  Abstract: Many systems have to be maintained while the underlying constraints, costs and/or profits change over time. Although the state of a system may evolve during time, a non-negligible transition cost is incured for transitioning from one state to another. In order to model such situations, Gupta et al. (ICALP 2014) and Eisenstat et al. (ICALP 2014) introduced a multistage model where the input is a sequence of instances (one for each time step), and the goal is to find a sequence of solutions (one for each time step) that are both (i) near optimal for each time step and (ii) as stable as possible. We focus on the multistage version of the Knapsack problem where we are given a time horizon t=1,2,...,T, and a sequence of knapsack instances I_1,I_2,...,I_T, one for each time step, defined on a set of n objects. In every time step t we have to choose a feasible knapsack S_t of I_t, which gives a knapsack profit. To measure the stability/similarity of two consecutive solutions S_t and S_{t+1}, we identify the objects for which the decision, to be picked or not, remains the same in S_t and S_{t+1}, giving a transition profit. We are asked to produce a sequence of solutions S_1,S_2,...,S_T so that the total knapsack profit plus the overall transition profit is maximized.  We propose a PTAS for the Multistage Knapsack problem. Then, we prove that there is no FPTAS for the problem even in the case where T=2, unless P=NP. Furthermore, we give a pseudopolynomial time algorithm for the case where the number of steps is bounded by a fixed constant and we show that otherwise the problem remains NP-hard even in the case where all the weights, profits and capacities are 0 or 1.

Connected through hyperedge HE-1 (induced by source paper "multistage graph problems on a global budget"):
  with members:
    - "multistage vertex cover"
    - "temporal matching"
    - "computing maximum matchings in temporal graphs"
    - "online multistage subset maximization problems"
    - "changing bases multistage optimization for matroids and matchings"
    - "facility location in evolving metrics"
    - "contracting graphs to paths and trees"

Connected through hyperedge HE-2 (induced by source paper "lp based algorithms for multistage minimization problems"):
  with members:
    - "multistage vertex cover"
    - "online multistage subset maximization problems"
    - "changing bases multistage optimization for matroids and matchings"
    - "facility location in evolving metrics"
    - "dynamic facility location via exponential clocks"
    - "the power of deferral maintaining a constant competitive steiner tree online"
    - "on the tradeoff between stability and fit"
    - "a new multilayered pcp and the hardness of hypergraph vertex cover"

Connected through hyperedge HE-3 (induced by source paper "multistage vertex cover"):
  with members:
    - "temporal vertex cover with a sliding time window"
    - "temporal graph classes a view through temporal separators"
    - "fast dynamic graph algorithms for parameterized problems"
    - "changing bases multistage optimization for matroids and matchings"
    - "the connectivity of boolean satisfiability computational and structural dichotomies"

Connected through hyperedge HE-4 (induced by source paper "multistage problems on a global budget"):
  with members:
    - "multistage vertex cover"
    - "online multistage subset maximization problems"
    - "changing bases multistage optimization for matroids and matchings"
    - "facility location in evolving metrics"
    - "contracting graphs to paths and trees"

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)