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: "a few graph based relational numerical abstract domains"
  Abstract: This article presents the systematic design of a class of relational numerical abstract domains from non-relational ones. Constructed domains represent sets of invariants of the form (vj - vi in C), where vj and vi are two variables, and C lives in an abstraction of P(Z), P(Q), or P(R). We will call this family of domains weakly relational domains. The underlying concept allowing this construction is an extension of potential graphs and shortest-path closure algorithms in exotic-like algebras. Example constructions are given in order to retrieve well-known domains as well as new ones. Such domains can then be used in the Abstract Interpretation framework in order to design various static analyses. Amajor benfit of this construction is its modularity, allowing to quickly implement new abstract domains from existing ones.

Connected through hyperedge HE-1 (induced by source paper "an improved tight closure algorithm for integer octagonal constraints"):
  with members:
    - "a new numerical abstract domain based on difference bound matrices"
    - "the octagon abstract domain"
    - "the parma polyhedra library toward a complete set of numerical abstractions for the analysis and verification of hardware and software systems"

Connected through hyperedge HE-2 (induced by source paper "the parallel implementation of the astree static analyzer"):
  with members:
    - "a new numerical abstract domain based on difference bound matrices"
    - "relational abstract domains for the detection of floating point run time errors"
    - "a static analyzer for large safety critical software"

Connected through hyperedge HE-3 (induced by source paper "widening operators for weakly relational numeric abstractions extended abstract"):
  with members:
    - "a new numerical abstract domain based on difference bound matrices"
    - "relational abstract domains for the detection of floating point run time errors"
    - "the octagon abstract domain"
    - "a static analyzer for large safety critical software"

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)