human: Given a hyperedge-centered hypergraph: <hypergraph>, where the center hyperedge is induced by one source paper and its member nodes are the cited papers.

Details of the hypergraph:
Center hyperedge (induced by source paper "catfish effect between internal and external attackers being semi honest is helpful"):
  Abstract: The consensus protocol named proof of work (PoW) is widely applied by cryptocurrencies like Bitcoin. Although security of a PoW cryptocurrency is always the top priority, it is threatened by mining attacks like selfish mining. Researchers have proposed many mining attack models with one attacker, and optimized the attacker's strategy. During these mining attacks, an attacker pursues a higher relative revenue (RR) by wasting a large amount of computational power of the honest miners at the cost of a small amount of computational power of himself. In this paper, we propose a mining attack model with two phases: the original system and the multi-attacker system. It is the first model to provide both theoretical and quantitative analysis of mining attacks with two attackers. We explain how the original system turns into the multi-attacker system by introducing two attackers: the internal attacker and the external attacker. If both attackers take the attacking strategy selfish mining, the RR of the internal attacker in multi-attacker system will drop by up to 31.9% compared with his RR in original system. The external attacker will overestimate his RR by up to 44.6% in multiattacker system. Unexpected competitions, auctions between attackers and overestimation of attackers' influence factor are three main causes of both attackers' dropping RR. We propose a mining strategy named Partial Initiative Release (PIR) which is a semi-honest mining strategy in multi-attacker system. In some specific situations, PIR allows the attacker to get more block reward by launching an attack in multi-attacker system.

Includes members:
  Member "be selfish and avoid dilemmas fork after withholding faw attacks on bitcoin":
    also connected through other hyperedges:
      - Hyperedge HE-1 (induced by source paper "exploring the attack surface of blockchain a systematic overview")
  Member "optimal selfish mining strategies in bitcoin":
    also connected through other hyperedges:
      - Hyperedge HE-2 (induced by source paper "incentive analysis of bitcoin ng revisited")
  Member "analysis of hashrate based double spending":
    also connected through other hyperedges:
      - Hyperedge HE-3 (induced by source paper "joint time scheduling and transaction fee selection in blockchain based rf powered backscatter cognitive radio network")
  Member "on subversive miner strategies and block withholding attack in bitcoin digital currency":
    also connected through other hyperedges:
      - Hyperedge HE-4 (induced by source paper "exploring the attack surface of blockchain a systematic overview")
  Member "the miner s dilemma":
    also connected through other hyperedges:
      - Hyperedge HE-5 (induced by source paper "surface a practical blockchain consensus algorithm for real world networks")
  Member "majority is not enough bitcoin mining is vulnerable":
    also connected through other hyperedges:
      - Hyperedge HE-6 (induced by source paper "on the convergence of artificial intelligence and distributed ledger technology a scoping review and future research agenda")

Question: Please tell me which class the source paper 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)