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: "characterizing code clones in the ethereum smart contract ecosystem"
  Abstract: In this paper, we present the first large-scale and systematic study to characterize the code reuse practice in the Ethereum smart contract ecosystem. We first performed a detailed similarity comparison study on a dataset of 10 million contracts we had harvested, and then we further conducted a qualitative analysis to characterize the diversity of the ecosystem, understand the correlation between code reuse and vulnerabilities, and detect the plagiarist DApps. Our analysis revealed that over 96% of the contracts had duplicates, while a large number of them were similar, which suggests that the ecosystem is highly homogeneous. Our results also suggested that roughly 9.7% of the similar contract pairs have exactly the same vulnerabilities, which we assume were introduced by code clones. In addition, we identified 41 DApps clusters, involving 73 plagiarized DApps which had caused huge financial loss to the original creators, accounting for 1/3 of the original market volume.

Connected through hyperedge HE-1 (induced by source paper "security analysis of eosio smart contracts"):
  with members:
    - "characterizing eosio blockchain"
    - "easyflow keep ethereum away from overflow"
    - "memory safety preservation for webassembly"
    - "a security case study for blockchain games"
    - "contractfuzzer fuzzing smart contracts for vulnerability detection"
    - "taintassembly taint based information flow control tracking for webassembly"
    - "wasabi a framework for dynamically analyzing webassembly"
    - "taint tracking for webassembly"

Connected through hyperedge HE-2 (induced by source paper "characterizing eosio blockchain"):
  with members:
    - "evulhunter detecting fake transfer vulnerabilities for eosio s smart contracts at webassembly level"
    - "contractfuzzer fuzzing smart contracts for vulnerability detection"
    - "securify practical security analysis of smart contracts"
    - "bitcoin transaction graph analysis"
    - "deanonymisation of clients in bitcoin p2p network"

Connected through hyperedge HE-3 (induced by source paper "wallet contracts on ethereum"):
  with members:
    - "an air gapped 2 factor authentication for smart contract wallets"

Connected through hyperedge HE-4 (induced by source paper "an empirical study into the success of listed smart contracts in ethereum"):
  with members:
    - "smart contracts software metrics a first study"
    - "blockchain oriented software engineering challenges and new directions"
    - "an empirical analysis of smart contracts platforms applications and design patterns"

Connected through hyperedge HE-5 (induced by source paper "smartembed a tool for clone and bug detection in smart contracts through structural code embedding"):
  with members:
    - "securify practical security analysis of smart contracts"
    - "enriching word vectors with subword information"

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)