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: "schaefer s theorem for graphs"
  Abstract: Schaefer's theorem is a complexity classification result for so-called Boolean constraint satisfaction problems: it states that every Boolean constraint satisfaction problem is either contained in one out of six classes and can be solved in polynomial time, or is NP-complete. #R##N#We present an analog of this dichotomy result for the propositional logic of graphs instead of Boolean logic. In this generalization of Schaefer's result, the input consists of a set W of variables and a conjunction \Phi\ of statements ("constraints") about these variables in the language of graphs, where each statement is taken from a fixed finite set \Psi\ of allowed quantifier-free first-order formulas; the question is whether \Phi\ is satisfiable in a graph. #R##N#We prove that either \Psi\ is contained in one out of 17 classes of graph formulas and the corresponding problem can be solved in polynomial time, or the problem is NP-complete. This is achieved by a universal-algebraic approach, which in turn allows us to use structural Ramsey theory. To apply the universal-algebraic approach, we formulate the computational problems under consideration as constraint satisfaction problems (CSPs) whose templates are first-order definable in the countably infinite random graph. Our method to classify the computational complexity of those CSPs is based on a Ramsey-theoretic analysis of functions acting on the random graph, and we develop general tools suitable for such an analysis which are of independent mathematical interest.

Connected through hyperedge HE-1 (induced by source paper "when symmetries are not enough a hierarchy of hard constraint satisfaction problems"):
  with members:
    - "topology is relevant in the infinite domain dichotomy conjecture for constraint satisfaction problems"
    - "a universal algebraic proof of the complexity dichotomy for monotone monadic snp"
    - "a dichotomy theorem for nonuniform csps"
    - "constraint satisfaction problems for reducts of homogeneous graphs"
    - "the algebraic dichotomy conjecture for infinite domain constraint satisfaction problems"
    - "complexity hierarchies beyond elementary"
    - "a complexity dichotomy for poset constraint satisfaction"

Connected through hyperedge HE-2 (induced by source paper "topology is relevant in a dichotomy conjecture for infinite domain constraint satisfaction problems"):
  with members:
    - "a universal algebraic proof of the complexity dichotomy for monotone monadic snp"
    - "algebraic approach to promise constraint satisfaction"
    - "a dichotomy theorem for nonuniform csps"
    - "the proof of csp dichotomy conjecture"
    - "constraint satisfaction problems for reducts of homogeneous graphs"
    - "the algebraic dichotomy conjecture for infinite domain constraint satisfaction problems"
    - "a complexity dichotomy for poset constraint satisfaction"
    - "equations in oligomorphic clones and the constraint satisfaction problem for omega categorical structures"

Connected through hyperedge HE-3 (induced by source paper "a hypergraph based approach for the 4 constraint satisfaction problem tractability"):
  with members:
    - "language emptiness of continuous time parametric timed automata"
    - "a new numerical abstract domain based on difference bound matrices"
    - "the octagon abstract domain"
    - "a static analyzer for large safety critical software"
    - "the essence of constraint propagation"

Connected through hyperedge HE-4 (induced by source paper "the complexity of disjunctive linear diophantine constraints"):
  with members:
    - "a dichotomy theorem for nonuniform csps"
    - "the proof of csp dichotomy conjecture"
    - "distance constraint satisfaction problems"
    - "constraint satisfaction and semilinear expansions of addition over the rationals and the reals"

Connected through hyperedge HE-5 (induced by source paper "classification transfer for qualitative reasoning problems"):
  with members:
    - "a dichotomy theorem for nonuniform csps"
    - "the proof of csp dichotomy conjecture"
    - "a survey of qualitative spatial and temporal calculi algebraic and computational properties"

Connected through hyperedge HE-6 (induced by source paper "distance constraint satisfaction problems"):
  with members:
    - "on the scope of the universal algebraic approach to constraint satisfaction"
    - "constraint satisfaction tractability from semi lattice operations on infinite sets"
    - "linear logic based analysis of constraint handling rules with disjunction"
    - "cores of countably categorical structures"
    - "adventures in time and space"

Connected through hyperedge HE-7 (induced by source paper "equations in oligomorphic clones and the constraint satisfaction problem for omega categorical structures"):
  with members:
    - "the algebraic dichotomy conjecture for infinite domain constraint satisfaction problems"
    - "a complexity dichotomy for poset constraint satisfaction"
    - "complexity classification in infinite domain constraint satisfaction"
    - "cores of countably categorical structures"

Connected through hyperedge HE-8 (induced by source paper "constraint satisfaction problems for reducts of homogeneous graphs"):
  with members:
    - "the complexity of phylogeny constraint satisfaction"
    - "complexity classification in infinite domain constraint satisfaction"
    - "cores of countably categorical structures"

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.CC(Computational Complexity)