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: "proposal for a fully decentralized blockchain and proof of work algorithm for solving np complete problems"
  Abstract: We propose a proof-of-work algorithm that rewards blockchain miners for using computational resources to solve NP-complete puzzles. The resulting blockchain will publicly store and improve solutions to problems with real world applications while maintaining a secure and fully functional transaction ledger.

Connected through hyperedge HE-1 (induced by source paper "incentive based integration of useful work into blockchains"):
  with members:
    - "revisiting distributed synchronous sgd"
    - "optimal selfish mining strategies in bitcoin"
    - "staleness aware async sgd for distributed deep learning"
    - "majority is not enough bitcoin mining is vulnerable"

Connected through hyperedge HE-2 (induced by source paper "difficulty scaling in proof of work for decentralized problem solving"):
  with members:
    - "incentive based integration of useful work into blockchains"
    - "coinami a cryptocurrency with dna sequence alignment as proof of work"

Connected through hyperedge HE-3 (induced by source paper "raziel private and verifiable smart contracts on blockchains"):
  with members:
    - "smotherspectre exploiting speculative execution through port contention"
    - "a systematic evaluation of transient execution attacks and defenses"
    - "cachezoom how sgx amplifies the power of cache attacks"
    - "chainspace a sharded smart contracts platform"
    - "an empirical analysis of smart contracts platforms applications and design patterns"
    - "software grand exposure sgx cache attacks are practical"
    - "rollback and forking detection for trusted execution environments using lightweight collective memory"
    - "malware guard extension using sgx to conceal cache 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.DC(Distributed, Parallel, and Cluster Computing)