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: "koka programming with row polymorphic effect types"
  Abstract: We propose a programming model where effects are treated in a disciplined way, and where the potential side-effects of a function are apparent in its type signature. The type and effect of expressions can also be inferred automatically, and we describe a polymorphic type inference system based on Hindley-Milner style inference. A novel feature is that we support polymorphic effects through row-polymorphism using duplicate labels. Moreover, we show that our effects are not just syntactic labels but have a deep semantic connection to the program. For example, if an expression can be typed without an exn effect, then it will never throw an unhandled exception. Similar to Haskell's `runST` we show how we can safely encapsulate stateful operations. Through the state effect, we can also safely combine state with let-polymorphism without needing either imperative type variables or a syntactic value restriction. Finally, our system is implemented fully in a new language called Koka and has been used successfully on various small to medium-sized sample programs ranging from a Markdown processor to a tier-splitted chat application. You can try out Koka live at www.rise4fun.com/koka/tutorial.

Connected through hyperedge HE-1 (induced by source paper "gradual typing for extensibility by rows"):
  with members:
    - "dynamic type inference for gradual hindley milner typing"
    - "gradual parametricity revisited"
    - "sums of uncertainty refinements go gradual"
    - "do be do be do"

Connected through hyperedge HE-2 (induced by source paper "calle an effect system for method calls"):
  with members:
    - "do be do be do"

Connected through hyperedge HE-3 (induced by source paper "sequential effect systems with control operators"):
  with members:
    - "an effect system for algebraic effects and handlers"
    - "the essence of javascript"

Connected through hyperedge HE-4 (induced by source paper "no value restriction is needed for algebraic effects and handlers"):
  with members:
    - "on the expressive power of user defined effects effect handlers monadic reflection delimited control"
    - "efficient algebraic effect handlers for prolog"
    - "do be do be do"
    - "trace semantics for polymorphic references"
    - "programming with algebraic effects and handlers"
    - "knowledge spaces and the completeness of learning strategies"
    - "inferring algebraic effects"
    - "an effect system for algebraic effects and handlers"

Connected through hyperedge HE-5 (induced by source paper "do be do be do"):
  with members:
    - "on the expressive power of user defined effects effect handlers monadic reflection delimited control"
    - "programming with algebraic effects and handlers"
    - "inferring algebraic effects"
    - "an effect system for algebraic effects and handlers"
    - "handling algebraic effects"
    - "programming interfaces and basic topology"

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)