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: "formal specification and verification of smart contracts for azure blockchain"
  Abstract: Ensuring correctness of smart contracts is paramount to ensuring trust in blockchain-based systems. This paper studies the safety and security of smart contracts in the \emph{Azure Blockchain Workbench}, an enterprise Blockchain-as-a-Service offering from Microsoft. As part of this study, we formalize \emph{semantic conformance} of smart contracts against a state machine model with access-control policy and develop a highly-automated formal verifier for Solidity that can produce proofs as well as counterexamples. We have applied our verifier {\sc VeriSol} to analyze {\it all} contracts shipped with the Azure Blockchain Workbench, which includes application samples as well as a governance contract for Proof of Authority (PoA). We have found previously unknown bugs in these published smart contracts. After fixing these bugs, {\sc VeriSol} was able to successfully perform full verification for all of these contracts.

Connected through hyperedge HE-1 (induced by source paper "formalising and verifying smart contracts with solidifier a bounded model checker for solidity"):
  with members:
    - "smt friendly formalization of the solidity memory model"
    - "ekiden a platform for confidentiality preserving trustworthy and performant smart contracts"
    - "solc verify a modular verifier for solidity smart contracts"
    - "a semantic framework for the security analysis of ethereum smart contracts"
    - "hyperledger fabric a distributed operating system for permissioned blockchains"
    - "securify practical security analysis of smart contracts"

Connected through hyperedge HE-2 (induced by source paper "smt friendly formalization of the solidity memory model"):
  with members:
    - "a survey on ethereum systems security vulnerabilities attacks and defenses"
    - "a minimal core calculus for solidity contracts"
    - "a semantic framework for the security analysis of ethereum smart contracts"
    - "executable operational semantics of solidity"

Connected through hyperedge HE-3 (induced by source paper "security analysis methods on ethereum smart contract vulnerabilities a survey"):
  with members:
    - "easyflow keep ethereum away from overflow"
    - "a security case study for blockchain games"
    - "a hybrid formal verification system in coq for ensuring the reliability and security of ethereum based service smart contracts"
    - "finding the greedy prodigal and suicidal contracts at scale"
    - "ethir a framework for high level analysis of ethereum bytecode"
    - "formal process virtual machine for smart contracts verification"
    - "scilla a smart contract intermediate level language"
    - "empirical vulnerability analysis of automated smart contracts security testing on blockchains"

Connected through hyperedge HE-4 (induced by source paper "empirical review of automated analysis tools on 47 587 ethereum smart contracts"):
  with members:
    - "a survey on ethereum systems security vulnerabilities attacks and defenses"
    - "the art of the scam demystifying honeypots in ethereum smart contracts"
    - "slither a static analysis framework for smart contracts"
    - "smart contract vulnerabilities does anyone care"
    - "domain specific code smells in smart contracts"
    - "manticore a user friendly symbolic execution framework for binaries and smart contracts"
    - "tool demonstration fsolidm for designing secure ethereum smart contracts"
    - "finding the greedy prodigal and suicidal contracts at scale"

Connected through hyperedge HE-5 (induced by source paper "oracle supported dynamic exploit generation for smart contracts"):
  with members:
    - "precise attack synthesis for smart contracts"
    - "exploiting the laws of order in smart contracts"
    - "finding the greedy prodigal and suicidal contracts at scale"
    - "sereum protecting existing smart contracts against re entrancy attacks"
    - "quantitative analysis of smart contracts"
    - "evaluating fuzz testing"
    - "contractfuzzer fuzzing smart contracts for vulnerability detection"
    - "learning inputs in greybox fuzzing"

Connected through hyperedge HE-6 (induced by source paper "verismart a highly precise safety verifier for ethereum smart contracts"):
  with members:
    - "finding the greedy prodigal and suicidal contracts at scale"
    - "online detection of effectively callback free objects with applications to smart contracts"
    - "gastap a gas analyzer for smart contracts"
    - "contractfuzzer fuzzing smart contracts for vulnerability detection"
    - "a semantic framework for the security analysis of ethereum smart contracts"
    - "vandal a scalable security analysis framework for smart contracts"
    - "securify practical security analysis of smart contracts"
    - "under optimized smart contracts devour your money"

Connected through hyperedge HE-7 (induced by source paper "performance analytical comparison of blockchain as a service baas platforms"):
  with members:
    - "lapps technological legal and market potentials of blockchain lightning network applications"
    - "atomic cross chain swaps development trajectory and potential of non monetary digital token swap facilities"
    - "applications of blockchain technology beyond cryptocurrency"
    - "application of blockchain in booking and registration systems of securities exchanges"
    - "a recruitment and human resource management technique using blockchain technology for industry 4 0"
    - "blockchain enabled enhanced iot ecosystem security"
    - "intercloud utility oriented federation of cloud computing environments for scaling of application services"

Connected through hyperedge HE-8 (induced by source paper "solc verify a modular verifier for solidity smart contracts"):
  with members:
    - "slither a static analysis framework for smart contracts"
    - "tool demonstration fsolidm for designing secure ethereum smart contracts"
    - "finding the greedy prodigal and suicidal contracts at scale"
    - "scilla a smart contract intermediate level language"
    - "a semantic framework for the security analysis of ethereum smart contracts"
    - "towards safer smart contracts a survey of languages and verification methods"
    - "securify practical security analysis of smart contracts"

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.PL(Programming Languages)