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: "collapsibility to a subcomplex of a given dimension is np complete"
  Abstract: In this paper we extend the works of Tancer, Malgouyres and Frances, showing that #N#                  #N#                    #N#                  #N#                  $$(d,k)$$#N#                  #N#                    #N#                  #N#                -Collapsibility is NP-complete for #N#                  #N#                    #N#                  #N#                  $$d\ge k+2$$#N#                  #N#                    #N#                  #N#                 except (2, 0). By #N#                  #N#                    #N#                  #N#                  $$(d,k)$$#N#                  #N#                    #N#                  #N#                -Collapsibility we mean the following problem: determine whether a given d-dimensional simplicial complex can be collapsed to some k-dimensional subcomplex. The question of establishing the complexity status of #N#                  #N#                    #N#                  #N#                  $$(d,k)$$#N#                  #N#                    #N#                  #N#                -Collapsibility was asked by Tancer, who proved NP-completeness of (d, 0) and #N#                  #N#                    #N#                  #N#                  $$(d,1)$$#N#                  #N#                    #N#                  #N#                -Collapsibility (for #N#                  #N#                    #N#                  #N#                  $$d\ge 3$$#N#                  #N#                    #N#                  #N#                ). Our extended result, together with the known polynomial-time algorithms for (2, 0) and #N#                  #N#                    #N#                  #N#                  $$d=k+1$$#N#                  #N#                    #N#                  #N#                , answers the question completely.

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.CG(Computational Geometry)