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 "simply ratt a fitch style modal calculus for reactive programming without space leaks"):
  Abstract: Functional reactive programming (FRP) is a paradigm for programming with signals and events, allowing the user to describe reactive programs on a high level of abstraction. For this to make sense, an FRP language must ensure that all programs are causal, and can be implemented without introducing space leaks and time leaks. To this end, some FRP languages do not give direct access to signals, but just to signal functions. #R##N#Recently, modal types have been suggested as an alternative approach to ensuring causality in FRP languages in the synchronous case, giving direct access to the signal and event abstractions. This paper presents Simply RaTT, a new modal calculus for reactive programming. Unlike prior calculi, Simply RaTT uses a Fitch-style approach to modal types, which simplifies the type system and makes programs more concise. Echoing a previous result by Krishnaswami for a different language, we devise an operational semantics that safely executes Simply RaTT programs without space leaks. #R##N#We also identify a source of time leaks present in other modal FRP languages: The unfolding of fixed points in delayed computations. These time leaks are eliminated by the Simply RaTT type system.

Includes members:
  Member "the clocks they are adjunctions denotational semantics for clocked type theory":
    also connected through other hyperedges:
      - Hyperedge HE-1 (induced by source paper "modal dependent type theory and dependent right adjoints")
  Member "a generalized modality for recursion":
    also connected through other hyperedges:
      - Hyperedge HE-2 (induced by source paper "diamonds are not forever liveness in reactive programming with guarded recursion")
  Member "modal dependent type theory and dependent right adjoints":
    also connected through other hyperedges:
      - Hyperedge HE-3 (induced by source paper "diamonds are not forever liveness in reactive programming with guarded recursion")
  Member "fitch style modal lambda calculi":
    also connected through other hyperedges:
      - Hyperedge HE-4 (induced by source paper "diamonds are not forever liveness in reactive programming with guarded recursion")
  Member "first steps in synthetic guarded domain theory step indexing in the topos of trees":
    also connected through other hyperedges:
      - Hyperedge HE-5 (induced by source paper "diamonds are not forever liveness in reactive programming with guarded recursion")

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.PL(Programming Languages)