human: Given a hyperedge-centered hypergraph: <hypergraph>, where the center hyperedge is induced by one source paper and its member nodes are the cited papers.

Details of the hypergraph:
Center hyperedge (induced by source paper "symbolic backwards reachability analysis for higher order pushdown systems"):
  Abstract: Higher-order pushdown systems (PDSs) generalise pushdown systems through the#N#use of higher-order stacks, that is, a nested "stack of stacks" structure.#N#These systems may be used to model higher-order programs and are closely#N#related to the Caucal hierarchy of infinite graphs and safe higher-order#N#recursion schemes.#N#  We consider the backwards-reachability problem over higher-order Alternating#N#PDSs (APDSs), a generalisation of higher-order PDSs. This builds on and extends#N#previous work on pushdown systems and context-free higher-order processes in a#N#non-trivial manner. In particular, we show that the set of configurations from#N#which a regular set of higher-order APDS configurations is reachable is regular#N#and computable in n-EXPTIME. In fact, the problem is n-EXPTIME-complete.#N#  We show that this work has several applications in the verification of#N#higher-order PDSs, such as linear-time model-checking, alternation-free#N#mu-calculus model-checking and the computation of winning regions of#N#reachability games.

Includes members:
  Member "symbolic reachability analysis of higher order context free processes":
    also connected through other hyperedges:
      - Hyperedge HE-1 (induced by source paper "annotated stack trees")
  Member "the complexity of games on higher order pushdown automata":
    also connected through other hyperedges:
      - Hyperedge HE-2 (induced by source paper "decision procedures for path feasibility of string manipulating programs with complex operations")

Question: Please tell me which class the source paper 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)