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: "underapproximation of procedure summaries for integer programs"
  Abstract: We show how to underapproximate the procedure summaries of recursive programs over the integers using off-the-shelf analyzers for non-recursive programs. The novelty of our approach is that the non-recursive program we compute may capture unboundedly many behaviors of the original recursive program for which stack usage cannot be bounded. Moreover, we identify a class of recursive programs on which our method terminates and returns the precise summary relations without underapproximation. Doing so, we generalize a similar result for non-recursive programs to the recursive case. Finally, we present experimental results of an implementation of our method applied on a number of examples.

Connected through hyperedge HE-1 (induced by source paper "a calculus for modular loop acceleration"):
  with members:
    - "on the decidability of termination for polynomial loops"
    - "proving non termination via loop acceleration"
    - "inferring lower runtime bounds for integer programs"
    - "on termination of integer linear loops"
    - "deciding conditional termination"
    - "abstract acceleration of general linear loops"
    - "abstracting path conditions"
    - "purrs towards computer algebra support for fully automatic worst case complexity analysis"

Connected through hyperedge HE-2 (induced by source paper "tree dimension in verification of constrained horn clauses"):
  with members:
    - "solving non linear horn clauses using a linear horn clause solver"
    - "proving correctness of imperative programs by linearizing constrained horn clauses"
    - "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-3 (induced by source paper "bounded oscillation pushdown automata"):
  with members:
    - "parikh s theorem a simple and direct automaton construction"
    - "approximating petri net reachability along context free traces"

Connected through hyperedge HE-4 (induced by source paper "interprocedural reachability for flat integer programs"):
  with members:
    - "safety problems are np complete for flat integer programs with octagonal loops"
    - "the reachability problem for vector addition systems with a stack is not elementary"
    - "taming past ltl and flat counter systems"
    - "an extension of parikh s theorem beyond idempotence"
    - "approximating petri net reachability along context free traces"
    - "the octagon abstract domain"

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)