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: "gtybalt a free computer algebra system"
  Abstract: Abstract   This article documents the free computer algebra system “gTybalt”. The program is build on top of other packages, among others GiNaC, TeXmacs and Root. It offers the possibility of interactive symbolic calculations within the C++ programming language. Mathematical formulae are visualized using     fonts.    Program summary   Title of program:  gTybalt   Version:  1.0.0   Catalogue identifier:  ADSI   Program summary URL:   http://cpc.cs.qub.ac.uk.summaries/ADSI    Program obtained from:  CPC Program Library, Queen's University of Belfast, N. Ireland   License:  GNU Public License   Computers:  all   Operating system:  GNU/Linux   Program language:  C++   Distribution format:  tar gzip file   No. of bytes in distributed program, including test data, etc.:  499583   Memory required to execute:  64 MB recommended   Other programs called:  see Appendix A   External files needed:  none   Keywords:  Symbolic calculations, Computer algebra   Nature of the physical problem:  Symbolic calculations occur nowadays in all areas of science. gTybalt is a free computer algebra system based on the C++ language.   Method of solution:  gTybalt is a “bazaar”-style program, it relies on existing, freely-available packages for specific sub-tasks.   Restrictions on complexity of the problem:  gTybalt does not try to cover every domain of mathematics. Some desirable algorithms, like symbolic integration are not implemented. It can however easily be extended in new directions. Apart from that, standard restrictions due to the available hardware apply.   Typical running time:  Depending on the complexity of the problem.

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.SC(Symbolic Computation)