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: "tree like queries in owl 2 ql succinctness and complexity results"
  Abstract: This paper investigates the impact of query topology on the difficulty of answering conjunctive queries in the presence of OWL 2 QL ontologies. Our first contribution is to clarify the worst-case size of positive existential (PE), non-recursive Datalog (NDL), and first-order (FO) rewritings for various classes of tree-like conjunctive queries, ranging from linear queries to bounded treewidth queries. Perhaps our most surprising result is a superpolynomial lower bound on the size of PE-rewritings that holds already for linear queries and ontologies of depth 2. More positively, we show that polynomial-size NDL-rewritings always exist for tree-shaped queries with a bounded number of leaves (and arbitrary ontologies), and for bounded treewidth queries paired with bounded depth ontologies. For FO-rewritings, we equate the existence of polysize rewritings with well-known problems in Boolean circuit complexity. As our second contribution, we analyze the computational complexity of query answering and establish tractability results (either NL- or LOGCFL-completeness) for a range of query-ontology pairs. Combining our new results with those from the literature yields a complete picture of the succinctness and complexity landscapes for the considered classes of queries and ontologies.

Connected through hyperedge HE-1 (induced by source paper "the complexity of ontology based data access with owl 2 ql and bounded treewidth queries"):
  with members:
    - "query rewriting and optimization for ontological databases"
    - "acyclicity notions for existential rules and their application to query answering in ontologies"
    - "sound complete and minimal ucq rewriting for existential rules"
    - "exponential lower bounds and separation for query rewriting"

Connected through hyperedge HE-2 (induced by source paper "ontology mediated queries combined complexity and succinctness of rewritings via circuit complexity"):
  with members:
    - "the complexity of ontology based data access with owl 2 ql and bounded treewidth queries"
    - "theoretically optimal datalog rewritings for owl 2 ql ontology mediated queries"
    - "datalog rewritability of disjunctive datalog programs and its applications to ontology reasoning"
    - "sound complete and minimal ucq rewriting for existential rules"
    - "ontology based data access a study through disjunctive datalog csp and mmsnp"
    - "exponential lower bounds and separation for query rewriting"
    - "rewriting ontological queries into small nonrecursive datalog programs"
    - "description logic tboxes model theoretic characterizations and rewritability"

Connected through hyperedge HE-3 (induced by source paper "theoretically optimal datalog rewritings for owl 2 ql ontology mediated queries"):
  with members:
    - "exponential lower bounds and separation for query rewriting"

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.AI(Artificial Intelligence)