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: "instruction sequence expressions for the secure hash algorithm sha 256"
  Abstract: The secure hash function SHA-256 is a function on bit strings. This means that its restriction to the bit strings of any given length can be computed by a finite instruction sequence that contains only instructions to set and get the content of Boolean registers, forward jump instructions, and a termination instruction. We describe such instruction sequences for the restrictions to bit strings of the different possible lengths by means of uniform terms from an algebraic theory.

Connected through hyperedge HE-1 (induced by source paper "program algebra for turing machine programs"):
  with members:
    - "on the complexity of the correctness problem for non zeroness test instruction sequences"
    - "instruction sequences expressing multiplication algorithms"
    - "a short introduction to program algebra with instructions for boolean registers"
    - "instruction sequence size complexity of parity"
    - "on algorithmic equivalence of instruction sequences for computing bit string functions"
    - "instruction sequence based non uniform complexity classes"
    - "instruction sequence processing operators"

Connected through hyperedge HE-2 (induced by source paper "instruction sequences expressing multiplication algorithms"):
  with members:
    - "instruction sequence size complexity of parity"
    - "on algorithmic equivalence of instruction sequences for computing bit string functions"
    - "instruction sequence based non uniform complexity classes"
    - "instruction sequence expressions for the karatsuba multiplication algorithm"
    - "long multiplication by instruction sequences with backward jump instructions"
    - "instruction sequence processing operators"
    - "on the expressiveness of single pass instruction sequences"
    - "indirect jumps improve instruction sequence performance"

Connected through hyperedge HE-3 (induced by source paper "on algorithmic equivalence of instruction sequences for computing bit string functions"):
  with members:
    - "instruction sequences expressing multiplication algorithms"
    - "instruction sequence based non uniform complexity classes"
    - "instruction sequence expressions for the karatsuba multiplication algorithm"
    - "long multiplication by instruction sequences with backward jump instructions"
    - "instruction sequence processing operators"
    - "program algebra with a jump shift instruction"
    - "when are two algorithms the same"

Connected through hyperedge HE-4 (induced by source paper "long multiplication by instruction sequences with backward jump instructions"):
  with members:
    - "instruction sequences expressing multiplication algorithms"
    - "on algorithmic equivalence of instruction sequences for computing bit string functions"
    - "instruction sequence based non uniform complexity classes"
    - "instruction sequence processing operators"
    - "on the contribution of backward jumps to instruction sequence expressiveness"
    - "an instruction sequence semigroup with involutive anti automorphisms"
    - "when are two algorithms the same"

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)