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: "how to charge lightning"
  Abstract: Off-chain transaction channels represent one of the leading techniques to scale the transaction throughput in cryptocurrencies. However, the economic effect of transaction channels on the system has not been explored much until now. We study the economics of Bitcoin transaction channels, and present a framework for an economic analysis of the lightning network and its effect on transaction fees on the blockchain. Our framework allows us to reason about different patterns of demand for transactions and different topologies of the lightning network, and to derive the resulting fees for transacting both on and off the blockchain. #R##N#Our initial results indicate that while the lightning network does allow for a substantially higher number of transactions to pass through the system, it does not necessarily provide higher fees to miners, and as a result may in fact lead to lower participation in mining within the system.

Connected through hyperedge HE-1 (induced by source paper "a cryptoeconomic traffic analysis of bitcoins lightning network"):
  with members:
    - "privacy utility tradeoffs in routing cryptocurrency over payment channel networks"
    - "topological analysis of bitcoin s lightning network"
    - "the evolution of lightning network s topology during its first year and the influence over its core values"
    - "payment networks as creation games"
    - "discharged payment channels quantifying the lightning network s resilience to topology based attacks"
    - "ant routing algorithm for the lightning network"
    - "payment network design with fees"
    - "towards an economic analysis of routing in payment channel networks"

Connected through hyperedge HE-2 (induced by source paper "how to profit from payments channels"):
  with members:
    - "discharged payment channels quantifying the lightning network s resilience to topology based attacks"
    - "celer network bring internet scale to every blockchain"
    - "payment network design with fees"
    - "towards an economic analysis of routing in payment channel networks"
    - "sprites and state channels payment networks that go faster than lightning"
    - "improving the betweenness centrality of a node by adding links"
    - "settling payments fast and private efficient decentralized routing for path based transactions"

Connected through hyperedge HE-3 (induced by source paper "a percolation model for the emergence of the bitcoin lightning network"):
  with members:
    - "a model of the optimal selection of crypto assets"
    - "topological analysis of bitcoin s lightning network"
    - "a cryptoeconomic traffic analysis of bitcoins lightning network"
    - "discharged payment channels quantifying the lightning network s resilience to topology based attacks"

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.CR(Cryptography and Security)