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: "eclipse from lp to clp"
  Abstract: ECLiPSe is a Prolog-based programming system, aimed at the development and deployment of constraint programming applications. It is also used for teaching most aspects of combinatorial problem solving, e.g. problem modelling, constraint programming, mathematical programming, and search techniques. It uses an extended Prolog as its high-level modelling and control language, complemented by several constraint solver libraries, interfaces to third-party solvers, an integrated development environment and interfaces for embedding into host environments. This paper discusses language extensions, implementation aspects, components and tools that we consider relevant on the way from Logic Programming to Constraint Logic Programming.

Connected through hyperedge HE-1 (induced by source paper "spacetime programming a synchronous language for composable search strategies"):
  with members:
    - "on the implementation of gnu prolog"
    - "efficient constraint propagation engines"
    - "the essence of constraint propagation"

Connected through hyperedge HE-2 (induced by source paper "exploiting term hiding to reduce run time checking overhead"):
  with members:
    - "practical run time checking via unobtrusive property caching"
    - "higher order symbolic execution via contracts"
    - "xsb extending prolog with tabled logic programming"
    - "sicstus prolog the first 25 years"

Connected through hyperedge HE-3 (induced by source paper "logic programming approaches for routing fault free and maximally parallel wavelength routed optical networks on chip application paper"):
  with members:
    - "a translational approach to constraint answer set solving"
    - "the dlv system for knowledge representation and reasoning"

Connected through hyperedge HE-4 (induced by source paper "concolic testing in logic programming"):
  with members:
    - "test case generation for object oriented imperative languages in clp"
    - "sicstus prolog the first 25 years"

Connected through hyperedge HE-5 (induced by source paper "the diamond system for argumentation preliminary report"):
  with members:
    - "on the acceptability of arguments in preference based argumentation"
    - "complex optimization in answer set programming"

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.PL(Programming Languages)