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 "piecewise testable languages and nondeterministic automata"):
  Abstract: A regular language is $k$-piecewise testable if it is a finite boolean combination of languages of the form $\Sigma^* a_1 \Sigma^* \cdots \Sigma^* a_n \Sigma^*$, where $a_i\in\Sigma$ and $0\le n \le k$. Given a DFA $A$ and $k\ge 0$, it is an NL-complete problem to decide whether the language $L(A)$ is piecewise testable and, for $k\ge 4$, it is coNP-complete to decide whether the language $L(A)$ is $k$-piecewise testable. It is known that the depth of the minimal DFA serves as an upper bound on $k$. Namely, if $L(A)$ is piecewise testable, then it is $k$-piecewise testable for $k$ equal to the depth of $A$. In this paper, we show that some form of nondeterminism does not violate this upper bound result. Specifically, we define a class of NFAs, called ptNFAs, that recognize piecewise testable languages and show that the depth of a ptNFA provides an (up to exponentially better) upper bound on $k$ than the minimal DFA. We provide an application of our result, discuss the relationship between $k$-piecewise testability and the depth of NFAs, and study the complexity of $k$-piecewise testability for ptNFAs.

Includes members:
  Member "on the index of simon s congruence for piecewise testability":
    also connected through other hyperedges:
      - Hyperedge HE-1 (induced by source paper "scattered factor universality of words")
  Member "on upper and lower bounds on the length of alternating towers":
    also connected through other hyperedges:
      - Hyperedge HE-2 (induced by source paper "on the height of towers of subsequences and prefixes")
  Member "alternating towers and piecewise testable separators":
    also connected through other hyperedges:
      - Hyperedge HE-3 (induced by source paper "testing simon s congruence")
  Member "separating regular languages by piecewise testable and unambiguous languages":
    also connected through other hyperedges:
      - Hyperedge HE-4 (induced by source paper "partially ordered automata and piecewise testability")
  Member "efficient separability of regular languages by subsequences and suffixes":
    also connected through other hyperedges:
      - Hyperedge HE-5 (induced by source paper "partially ordered automata and piecewise testability")
  Member "piecewise testable tree languages":
    also connected through other hyperedges:
      - Hyperedge HE-6 (induced by source paper "partially ordered automata and piecewise testability")
  Member "around dot depth one":
    also connected through other hyperedges:
      - Hyperedge HE-7 (induced by source paper "adding successor a transfer theorem for separation and covering")

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.FL(Formal Languages and Automata Theory)