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: "on the relation between context free grammars and parsing expression grammars"
  Abstract: Abstract   Context-Free Grammars (CFGs) and Parsing Expression Grammars (PEGs) have several similarities and a few differences in both their syntax and semantics, but they are usually presented through formalisms that hinder a proper comparison. In this paper we present a new formalism for CFGs that highlights the similarities and differences between them. The new formalism borrows from PEGs the use of parsing expressions and the recognition-based semantics. We show how one way of removing non-determinism from this formalism yields a formalism with the semantics of PEGs. We also prove, based on these new formalisms, how     LL   (  1  )    grammars define the same language whether interpreted as CFGs or as PEGs, and also show how strong-    LL   (  k  )   , right-linear, and LL-regular grammars have simple language-preserving translations from CFGs to PEGs. Once these classes of CFGs can be automatically translated to equivalent PEGs, we can reuse classic top-down grammars in PEG-based tools.

Connected through hyperedge HE-1 (induced by source paper "automatic syntax error reporting and recovery in parsing expression grammars"):
  with members:
    - "simplified parsing expression derivatives"
    - "syntax error recovery in parsing expression grammars"
    - "recognising and generating terms using derivatives of parsing expression grammars"

Connected through hyperedge HE-2 (induced by source paper "a semi automatic approach for syntax error reporting and recovery in parsing expression grammars"):
  with members:
    - "syntax error recovery in parsing expression grammars"

Connected through hyperedge HE-3 (induced by source paper "error reporting in parsing expression grammars"):
  with members:
    - "left recursion in parsing expression grammars"
    - "packrat parsing simple powerful lazy linear time"

Connected through hyperedge HE-4 (induced by source paper "left recursion in parsing expression grammars"):
  with members:
    - "packrat parsing simple powerful lazy linear time"

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.FL(Formal Languages and Automata Theory)