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: "a fully polynomial time approximation scheme for packing while traveling"
  Abstract: Understanding the interactions between different combinatorial optimisation problems in real-world applications is a challenging task. Recently, the traveling thief problem (TTP), as a combination of the classical traveling salesperson problem and the knapsack problem, has been introduced to study these interactions in a systematic way. We investigate the underlying non-linear packing while traveling (PWT) problem of the TTP where items have to be selected along a fixed route. We give an exact dynamic programming approach for this problem and a fully polynomial time approximation scheme (FPTAS) when maximising the benefit that can be gained over the baseline travel cost. Our experimental investigations show that our new approaches outperform current state-of-the-art approaches on a wide range of benchmark instances.

Connected through hyperedge HE-1 (induced by source paper "the node weight dependent traveling salesperson problem approximation algorithms and randomized search heuristics"):
  with members:
    - "evolutionary computation plus dynamic programming for the bi objective travelling thief problem"
    - "exact approaches for the travelling thief problem"
    - "a case study of algorithm selection for the traveling thief problem"
    - "evolutionary computation for multicomponent problems opportunities and future directions"

Connected through hyperedge HE-2 (induced by source paper "a non dominated sorting based customized random key genetic algorithm for the bi objective traveling thief problem"):
  with members:
    - "evolutionary computation plus dynamic programming for the bi objective travelling thief problem"
    - "exact approaches for the travelling thief problem"
    - "a case study of algorithm selection for the traveling thief problem"

Connected through hyperedge HE-3 (induced by source paper "analysis of baseline evolutionary algorithms for the packing while travelling problem"):
  with members:
    - "precise runtime analysis for plateaus"
    - "evolutionary computation for multicomponent problems opportunities and future directions"
    - "the packing while traveling problem"
    - "packing while traveling mixed integer programming for a class of nonlinear knapsack problems"

Connected through hyperedge HE-4 (induced by source paper "evolutionary computation plus dynamic programming for the bi objective travelling thief problem"):
  with members:
    - "exact approaches for the travelling thief problem"
    - "a case study of algorithm selection for the traveling thief problem"
    - "the packing while traveling problem"

Connected through hyperedge HE-5 (induced by source paper "exact approaches for the travelling thief problem"):
  with members:
    - "a case study of algorithm selection for the traveling thief problem"
    - "cosolver2b an efficient local search heuristic for the travelling thief problem"
    - "the packing while traveling problem"

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)