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: "loop patterns extension of kleene star operator for more expressive pattern matching against arbitrary data structures"
  Abstract: The Kleene star operator is an important pattern construct for representing a pattern that repeats multiple times. Due to its simplicity and usefulness, it is imported into various pattern-matching systems other than regular expressions. For example, Mathematica has a similar pattern construct called the repeated pattern. However, they have the following limitations: (i) We cannot change the pattern repeated depending on the current repeat count, and (ii) we cannot apply them to arbitrary data structures such as trees and graphs other than lists. This paper proposes the loop patterns that overcome these limitations. This paper presents numerous working examples and formal semantics of the loop patterns. The examples in this paper are coded in the Egison programming language, which features the customizable non-linear pattern-matching facility for non-free data types.

Connected through hyperedge HE-1 (induced by source paper "functional programming in pattern match oriented programming style"):
  with members:
    - "non linear pattern matching with backtracking for non free data types"
    - "scalar and tensor parameters for importing tensor index notation including einstein summation notation"
    - "the gremlin graph traversal machine and language invited talk"
    - "extensible pattern matching in an extensible language"
    - "semantics and complexity of sparql"

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)