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: "complete and easy bidirectional typechecking for higher rank polymorphism"
  Abstract: Bidirectional typechecking, in which terms either synthesize a type or are checked against a known type, has become popular for its scalability (unlike Damas-Milner type inference, bidirectional typing remains decidable even for very expressive type systems), its error reporting, and its relative ease of implementation. Following design principles from proof theory, bidirectional typing can be applied to many type constructs. The principles underlying a bidirectional approach to polymorphism, however, are less obvious. We give a declarative, bidirectional account of higher-rank polymorphism, grounded in proof theory; this calculus enjoys many properties such as eta-reduction and predictability of annotations. We give an algorithm for implementing the declarative system; our algorithm is remarkably simple and well-behaved, despite being both sound and complete.

Connected through hyperedge HE-1 (induced by source paper "signature restriction for polymorphic algebraic effects"):
  with members:
    - "handling polymorphic algebraic effects"
    - "no value restriction is needed for algebraic effects and handlers"
    - "do be do be do"
    - "programming with algebraic effects and handlers"
    - "handling algebraic effects"

Connected through hyperedge HE-2 (induced by source paper "kind inference for datatypes"):
  with members:
    - "dependent types in haskell theory and practice"

Connected through hyperedge HE-3 (induced by source paper "label dependent session types"):
  with members:
    - "depending on session typed processes"
    - "dependent session types"
    - "recalling a witness foundations and applications of monotonic state"
    - "linear haskell practical linearity in a higher order polymorphic language"
    - "set theoretic types for polymorphic variants"
    - "sessions as propositions"
    - "irrelevance heterogeneous equality and call by value dependent type systems"
    - "linear dependent types and relative completeness"

Connected through hyperedge HE-4 (induced by source paper "live functional programming with typed holes"):
  with members:
    - "exploratory and live programming and coding a literature study comparing perspectives on liveness"
    - "augmenting source code lines with sample variable values"
    - "using elm to introduce algebraic thinking to k 8 students"
    - "imperative functional programs that explain their work"
    - "toward semantic foundations for program editors"
    - "a survey of symbolic execution techniques"
    - "dynamic witnesses for static type errors or ill typed programs usually go wrong"
    - "programmatic and direct manipulation together at last"

Connected through hyperedge HE-5 (induced by source paper "a theory of linear typings as flows on 3 valent graphs"):
  with members:
    - "linear lambda terms as invariants of rooted trivalent maps"
    - "counting isomorphism classes of β normal linear lambda terms"
    - "a correspondence between rooted planar maps and normal planar lambda terms"
    - "graphic lambda calculus"

Connected through hyperedge HE-6 (induced by source paper "fungi typed incremental computation with names"):
  with members:
    - "toward semantic foundations for program editors"
    - "reactive imperative programming with dataflow constraints"

Connected through hyperedge HE-7 (induced by source paper "constraint handling rules with binders patterns and generic quantification"):
  with members:
    - "as time goes by constraint handling rules a survey of chr research from 1998 to 2007"

Connected through hyperedge HE-8 (induced by source paper "sound and complete bidirectional typechecking for higher rank polymorphism with existentials and indexed types"):
  with members:
    - "gadts and exhaustiveness looking for the impossible"
    - "phantom types and subtyping"

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)