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: "sparsest cut on bounded treewidth graphs algorithms and hardness results"
  Abstract: We give a 2-approximation algorithm for Non-Uniform Sparsest Cut that runs in time $n^{O(k)}$, where $k$ is the treewidth of the graph. This improves on the previous $2^{2^k}$-approximation in time $\poly(n) 2^{O(k)}$ due to Chlamt\'a\v{c} et al. #R##N#To complement this algorithm, we show the following hardness results: If the Non-Uniform Sparsest Cut problem has a $\rho$-approximation for series-parallel graphs (where $\rho \geq 1$), then the Max Cut problem has an algorithm with approximation factor arbitrarily close to $1/\rho$. Hence, even for such restricted graphs (which have treewidth 2), the Sparsest Cut problem is NP-hard to approximate better than $17/16 - \epsilon$ for $\epsilon > 0$; assuming the Unique Games Conjecture the hardness becomes $1/\alpha_{GW} - \epsilon$. For graphs with large (but constant) treewidth, we show a hardness result of $2 - \epsilon$ assuming the Unique Games Conjecture. #R##N#Our algorithm rounds a linear program based on (a subset of) the Sherali-Adams lift of the standard Sparsest Cut LP. We show that even for treewidth-2 graphs, the LP has an integrality gap close to 2 even after polynomially many rounds of Sherali-Adams. Hence our approach cannot be improved even on such restricted graphs without using a stronger relaxation.

Connected through hyperedge HE-1 (induced by source paper "on the parameterized complexity of sparsest cut and small set expansion problems"):
  with members:
    - "an o log 1 5 n log log n approximation algorithm for mean isoperimetry and robust k means"

Connected through hyperedge HE-2 (induced by source paper "integrality gaps for bounded color matchings"):
  with members:
    - "a birthday repetition theorem and complexity of approximating dense csps"
    - "lift and round to improve weighted completion time on unrelated machines"
    - "generalized hypergraph matching via iterated packing and local ratio"
    - "complexity results for rainbow matchings"
    - "on integrality ratios for asymmetric tsp in the sherali adams hierarchy"
    - "iterative packing for demand and hypergraph matching"
    - "approximating sparsest cut in graphs of bounded treewidth"

Connected through hyperedge HE-3 (induced by source paper "survivable network design for group connectivity in low treewidth graphs"):
  with members:
    - "a polynomial time approximation scheme for euclidean steiner forest"
    - "parameters of two prover one round game and the hardness of connectivity problems"
    - "an improved approximation algorithm for the minimum cost subset k connected subgraph problem"
    - "solving connectivity problems parameterized by treewidth in single exponential time"
    - "polynomial time approximation schemes for subset connectivity problems in bounded genus graphs"
    - "approximation schemes for steiner forest on planar graphs and graphs of bounded treewidth"
    - "an o k 3 log n approximation algorithm for vertex connectivity survivable network design"

Connected through hyperedge HE-4 (induced by source paper "randomly coloring graphs of bounded treewidth"):
  with members:
    - "rapidly mixing markov chains a comparison of techniques a survey"
    - "an fptas for counting proper four colorings on cubic graphs"
    - "random cluster dynamics for the ising model is rapidly mixing"
    - "known algorithms on graphs of bounded treewidth are probably optimal"

Connected through hyperedge HE-5 (induced by source paper "metric embedding via shortest path decompositions"):
  with members:
    - "metric decompositions of path separable graphs"
    - "cops robbers and threatening skeletons padded decomposition for minor free graphs"
    - "measured descent a new embedding method for finite metrics"

Connected through hyperedge HE-6 (induced by source paper "recognizing hyperelliptic graphs in polynomial time"):
  with members:
    - "graph isomorphism in quasipolynomial time"

Connected through hyperedge HE-7 (induced by source paper "strong reductions for extended formulations"):
  with members:
    - "approximating rectangles by juntas and weakly exponential lower bounds for lp relaxations of csps"
    - "the matching polytope does not admit fully polynomial size relaxation schemes"
    - "extension complexity mso logic and treewidth"
    - "no small linear program approximates vertex cover within a factor 2 epsilon"
    - "lower bounds on the size of semidefinite programming relaxations"
    - "approximate constraint satisfaction requires large lp relaxations"
    - "the matching polytope has exponential extension complexity"
    - "approximation limits of linear programs beyond hierarchies"

Connected through hyperedge HE-8 (induced by source paper "max cut under graph constraints"):
  with members:
    - "approximation algorithms for connected maximum cut and related problems"
    - "submodular function maximization via the multilinear relaxation and contention resolution schemes"

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.DS(Data Structures and Algorithms)