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: "applying constraint handling rules to hpsg"
  Abstract: Constraint Handling Rules (CHR) have provided a realistic solution to an over-arching problem in many fields that deal with constraint logic programming: how to combine recursive functions or relations with constraints while avoiding non-termination problems. This paper focuses on some other benefits that CHR, specifically their implementation in SICStus Prolog, have provided to computational linguists working on grammar design tools. CHR rules are applied by means of a subsumption check and this check is made only when their variables are instantiated or bound. The former functionality is at best difficult to simulate using more primitive coroutining statements such as SICStus when/2, and the latter simply did not exist in any form before CHR. #R##N#For the sake of providing a case study in how these can be applied to grammar development, we consider the Attribute Logic Engine (ALE), a Prolog preprocessor for logic programming with typed feature structures, and its extension to a complete grammar development system for Head-driven Phrase Structure Grammar (HPSG), a popular constraint-based linguistic theory that uses typed feature structures. In this context, CHR can be used not only to extend the constraint language of feature structure descriptions to include relations in a declarative way, but also to provide support for constraints with complex antecedents and constraints on the co-occurrence of feature values that are necessary to interpret the type system of HPSG properly.

Connected through hyperedge HE-1 (induced by source paper "as time goes by constraint handling rules a survey of chr research from 1998 to 2007"):
  with members:
    - "linear logic based analysis of constraint handling rules with disjunction"
    - "a compositional semantics for chr"
    - "acd term rewriting"
    - "automatic generation of chr constraint solvers"
    - "optimizing compilation of constraint handling rules in hal"
    - "a chr based implementation of known arc consistency"
    - "intelligent search strategies based on adaptive constraint handling rules"
    - "flux a logic programming method for reasoning agents"

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.CL(Computation and Language)