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: "efficient expression templates for operator overloading based automatic differentiation"
  Abstract: Expression templates are a well-known set of techniques for improving the efficiency of operator overloading-based forward mode automatic differentiation schemes in the C\(++\) programming language by translating the differentiation from individual operators to whole expressions. However standard expression template approaches result in a large amount of duplicate computation, particularly for large expression trees, degrading their performance. In this paper we describe several techniques for improving the efficiency of expression templates and their implementation in the automatic differentiation package Sacado (Phipps et al., Advances in automatic differentiation, Lecture notes in computational science and engineering, Springer, Berlin, 2008; Phipps and Gay, Sacado automatic differentiation package. http://trilinos.sandia.gov/packages/sacado/, 2011). We demonstrate their improved efficiency through test functions as well as their application to differentiation of a large-scale fluid dynamics simulation code.

Connected through hyperedge HE-1 (induced by source paper "the deal ii finite element library design features and insights"):
  with members:
    - "parallel tree algorithms for amr and non standard data access"
    - "fast matrix free evaluation of discontinuous galerkin finite element operators"

Connected through hyperedge HE-2 (induced by source paper "a review of automatic differentiation and its efficient implementation"):
  with members:
    - "high performance derivative computations using codipack"
    - "tensorflow large scale machine learning on heterogeneous distributed systems"
    - "the stan math library reverse mode automatic differentiation in c"

Connected through hyperedge HE-3 (induced by source paper "manifold geometry with fast automatic derivatives and coordinate frame semantics checking in c"):
  with members:
    - "a primer on the differential calculus of 3d orientations"
    - "automatic differentiation in machine learning a survey"
    - "the stan math library reverse mode automatic differentiation in c"
    - "expression templates revisited a performance analysis of current methodologies"
    - "integrating generic sensor fusion algorithms with sound state representations through encapsulation of manifolds"

Connected through hyperedge HE-4 (induced by source paper "automating embedded analysis capabilities and managing software complexity in multiphysics simulation part i template based generic programming"):
  with members:
    - "expression templates revisited a performance analysis of current methodologies"
    - "automating embedded analysis capabilities and managing software complexity in multiphysics simulation part ii application to partial differential equations"

Connected through hyperedge HE-5 (induced by source paper "automating embedded analysis capabilities and managing software complexity in multiphysics simulation part ii application to partial differential equations"):
  with members:
    - "automating embedded analysis capabilities and managing software complexity in multiphysics simulation part i template based generic programming"
    - "analysis of and workarounds for element reversal for a finite element based algorithm for warping triangular and tetrahedral meshes"

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.MS(Mathematical Software)