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: "the road coloring problem"
  Abstract: The synchronizing word of deterministic automaton is a word in the alphabet of colors (considered as letters) of its edges that maps the automaton to a single state. A coloring of edges of a directed graph is synchronizing if the coloring turns the graph into deterministic finite automaton possessing a synchronizing word. #R##N#The road coloring problem is a problem of synchronizing coloring of directed finite strongly connected graph with constant outdegree of all its vertices if the greatest common divisor of lengths of all its cycles is one. The problem was posed by Adler, Goodwyn and Weiss over 30 years ago and evoked a noticeable interest among the specialists in theory of graphs, deterministic automata and symbolic dynamics. The problem is described even in "Wikipedia" - the popular Internet Encyclopedia. The positive solution of the road coloring problem is presented.

Connected through hyperedge HE-1 (induced by source paper "synchronizing random almost group automata"):
  with members:
    - "improving the upper bound on the length of the shortest reset word"
    - "fast synchronization of random automata"
    - "on the probability of being synchronizable"

Connected through hyperedge HE-2 (induced by source paper "on incomplete and synchronizing finite sets"):
  with members:
    - "on non complete sets and restivo s conjecture"
    - "independent sets of words and the synchronization problem"
    - "on the minimal uncompletable word problem"
    - "slowly synchronizing automata and digraphs"

Connected through hyperedge HE-3 (induced by source paper "completely reachable automata"):
  with members:
    - "reset complexity of ideal languages"
    - "syntactic complexity of r and j trivial regular languages"
    - "primitive digraphs with large exponents and slowly synchronizing automata"

Connected through hyperedge HE-4 (induced by source paper "on the number of synchronizing colorings of digraphs"):
  with members:
    - "complexity of road coloring with prescribed reset words"
    - "reset thresholds of automata with two cycle lengths"
    - "fast synchronization of random automata"
    - "synchronizing automata with large reset lengths"
    - "primitive digraphs with large exponents and slowly synchronizing automata"
    - "on the probability of being synchronizable"
    - "practical graph isomorphism ii"
    - "a quadratic algorithm for road coloring"

Connected through hyperedge HE-5 (induced by source paper "reachability of consensus and synchronizing automata"):
  with members:
    - "on the synchronizing probability function and the triple rendezvous time for synchronizing automata"
    - "efficient algorithms for the consensus decision problem"
    - "p l aying for synchronization"
    - "approximating the minimum length of synchronizing words is hard"

Connected through hyperedge HE-6 (induced by source paper "synchronizing automata and principal eigenvectors of the underlying digraphs"):
  with members:
    - "on the number of synchronizing colorings of digraphs"
    - "primitive digraphs with large exponents and slowly synchronizing automata"

Connected through hyperedge HE-7 (induced by source paper "complexity of road coloring with prescribed reset words"):
  with members:
    - "on the number of synchronizing colorings of digraphs"
    - "a note on a recent attempt to improve the pin frankl bound"
    - "parameterized complexity of synchronization and road coloring"
    - "strong inapproximability of the shortest reset word"
    - "an algorithm for road coloring"
    - "a quadratic algorithm for road coloring"

Connected through hyperedge HE-8 (induced by source paper "testing for synchronization"):
  with members:
    - "on the probability to be synchronizable"
    - "on two algorithmic problems about synchronizing automata"
    - "on the probability of being synchronizable"
    - "the complexity of finding reset words in finite automata"
    - "approximating the minimum length of synchronizing words is hard"

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.DM(Discrete Mathematics)