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: "integer vector addition systems with states"
  Abstract: This paper studies reachability, coverability and inclusion problems for Integer Vector Addition Systems with States (ℤ-VASS) and extensions and restrictions thereof. A ℤ-VASS comprises a finite-state controller with a finite number of counters ranging over the integers. Although it is folklore that reachability in ℤ-VASS is NP-complete, it turns out that despite their naturalness, from a complexity point of view this class has received little attention in the literature. We fill this gap by providing an in-depth analysis of the computational complexity of the aforementioned decision problems. Most interestingly, it turns out that while the addition of reset operations to ordinary VASS leads to undecidability and Ackermann-hardness of reachability and coverability, respectively, they can be added to ℤ-VASS while retaining NP-completeness of both coverability and reachability.

Connected through hyperedge HE-1 (induced by source paper "on affine reachability problems"):
  with members:
    - "on the complexity of the orbit problem"

Connected through hyperedge HE-2 (induced by source paper "affine extensions of integer vector addition systems with states"):
  with members:
    - "the reachability problem for petri nets is not elementary"
    - "how hard is it to verify flat affine counter systems with the finite monoid property"
    - "reachability in two dimensional vector addition systems with states is pspace complete"
    - "regular combinators for string transformations"
    - "decision problems for additive regular functions"
    - "ackermannian and primitive recursive bounds with dickson s lemma"
    - "bounded parikh automata"

Connected through hyperedge HE-3 (induced by source paper "loop summarization with rational vector addition systems extended version"):
  with members:
    - "invariant generation for multi path loops with polynomial assignments"
    - "polynomial invariants for affine programs"
    - "approaching the coverability problem continuously"
    - "a simple and scalable static analysis for bound analysis and amortized complexity analysis"
    - "a quantifier elimination algorithm for linear real arithmetic"

Connected through hyperedge HE-4 (induced by source paper "the well structured problem for presburger counter machines"):
  with members:
    - "the complexity of reachability in affine vector addition systems with states"
    - "affine extensions of integer vector addition systems with states"
    - "the universal fragment of presburger arithmetic with unary uninterpreted predicates is undecidable"

Connected through hyperedge HE-5 (induced by source paper "costs and rewards in priced timed automata"):
  with members:
    - "parikh images of regular languages complexity and applications"

Connected through hyperedge HE-6 (induced by source paper "register automata with linear arithmetic"):
  with members:
    - "the commutativity problem of the mapreduce framework a transducer based approach"
    - "relating timed and register automata"
    - "ltl with the freeze quantifier and register automata"

Connected through hyperedge HE-7 (induced by source paper "well behaved transition systems"):
  with members:
    - "reachability in two dimensional vector addition systems with states is pspace complete"
    - "context free commutative grammars with integer counters and resets"
    - "fixed dimensional energy games are in pseudo polynomial time"
    - "kleene algebras and semimodules for energy problems"
    - "the power of well structured systems"
    - "forward analysis for wsts part ii complete wsts"
    - "multiply recursive upper bounds with higman s lemma"
    - "forward analysis for wsts part i completions"

Connected through hyperedge HE-8 (induced by source paper "linear combinations of unordered data vectors"):
  with members:
    - "model checking flat freeze ltl on one counter automata"
    - "approaching the coverability problem continuously"
    - "homogeneous equations of algebraic petri nets"
    - "demystifying reachability in vector addition systems"
    - "automata theory in nominal sets"
    - "the power of well structured systems"

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)