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: "digraph decompositions and monotonicity in digraph searching"
  Abstract: We consider monotonicity problems for graph searching games. Variants of these games - defined by the type of moves allowed for the players - have been found to be closely connected to graph decompositions and associated width measures such as path- or tree-width. Of particular interest is the question whether these games are monotone, i.e. whether the cops can catch a robber without ever allowing the robber to reach positions that have been cleared before. The monotonicity problem for graph searching games has intensely been studied in the literature, but for two types of games the problem was left unresolved. These are the games on digraphs where the robber is invisible and lazy or visible and fast. In this paper, we solve the problems by giving examples showing that both types of games are non-monotone. Graph searching games on digraphs are closely related to recent proposals for digraph decompositions generalising tree-width to directed graphs. These proposals have partly been motivated by attempts to develop a structure theory for digraphs similar to the graph minor theory developed by Robertson and Seymour for undirected graphs, and partly by the immense number of algorithmic results using tree-width of undirected graphs and the hope that part of this success might be reproducible on digraphs using a directed tree-width. Unfortunately the number of applications for the digraphs measures introduced so far is still small. We therefore explore the limits of the algorithmic applicability of digraph decompositions. In particular, we show that various natural candidates for problems that might benefit from digraphs having small directed tree-width remain NP-complete even on almost acyclic graphs.

Connected through hyperedge HE-1 (induced by source paper "directed width measures and monotonicity of directed graph searching"):
  with members:
    - "a trichotomy for regular simple path queries on graphs"
    - "graph searching parity games and imperfect information"

Connected through hyperedge HE-2 (induced by source paper "the planar directed k vertex disjoint paths problem is fixed parameter tractable"):
  with members:
    - "finding topological subgraphs is fixed parameter tractable"
    - "are there any good digraph width measures"

Connected through hyperedge HE-3 (induced by source paper "tree width for first order formulae"):
  with members:
    - "constraint solving via fractional edge covers"
    - "hypertree decompositions and tractable queries"

Connected through hyperedge HE-4 (induced by source paper "directed nowhere dense classes of graphs"):
  with members:
    - "are there any good digraph width measures"
    - "domination problems in nowhere dense classes of graphs"
    - "homomorphism preservation on quasi wide classes"
    - "on complexity of minimum leaf out branching problem"

Connected through hyperedge HE-5 (induced by source paper "digraph complexity measures and applications in formal language theory"):
  with members:
    - "lifo search on digraphs a searching game for cycle rank"
    - "on balanced separators treewidth and cycle rank"

Connected through hyperedge HE-6 (induced by source paper "lifo search on digraphs a searching game for cycle rank"):
  with members:
    - "digraph complexity measures and applications in formal language theory"

Connected through hyperedge HE-7 (induced by source paper "graph searching parity games and imperfect information"):
  with members:
    - "algorithms for omega regular games with imperfect information"

Connected through hyperedge HE-8 (induced by source paper "games for width parameters and monotonicity"):
  with members:
    - "constraint solving via fractional edge covers"
    - "partitions versus sets a case of duality"

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)