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: "sparsification and subexponential approximation"
  Abstract: Instance sparsification is well-known in the world of exact computation since it is very closely linked to the Exponential Time Hypothesis. In this paper, we extend the concept of sparsification in order to capture subexponential time approximation. We develop a new tool for inapproximability, called approximation preserving sparsification and use it in order to get strong inapproximability results in subexponential time for several fundamental optimization problems as Max Independent Set, Min Dominating Set, Min Feedback Vertex Set, and Min Set Cover.

Connected through hyperedge HE-1 (induced by source paper "new tools and connections for exponential time approximation"):
  with members:
    - "from gap eth to fpt inapproximability clique dominating set and more"
    - "a birthday repetition theorem and complexity of approximating dense csps"
    - "time approximation trade offs for inapproximable problems"
    - "independent set induced matching and pricing connections and tight subexponential time approximation hardnesses"
    - "exponential time approximation of hard problems"

Connected through hyperedge HE-2 (induced by source paper "lower bounds for the parameterized complexity of minimum fill in and other completion problems"):
  with members:
    - "time approximation trade offs for inapproximable problems"
    - "on the threshold of intractability"
    - "a polynomial kernel for trivially perfect editing"
    - "a subexponential parameterized algorithm for proper interval completion"
    - "a subexponential parameterized algorithm for interval completion"
    - "exploring subexponential parameterized complexity of completion problems"
    - "parameterized in approximability of subset problems"
    - "subexponential parameterized algorithm for minimum fill in"

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.CC(Computational Complexity)