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: "computing tree depth faster than 2 n"
  Abstract: A connected graph has tree-depth at most $k$ if it is a subgraph of the closure of a rooted tree whose height is at most $k$. We give an algorithm which for a given $n$-vertex graph $G$, in time $\mathcal{O}(1.9602^n)$ computes the tree-depth of $G$. Our algorithm is based on combinatorial results revealing the structure of minimal rooted trees whose closures contain $G$.

Connected through hyperedge HE-1 (induced by source paper "sat encodings for treecut width and treedepth"):
  with members:
    - "a parameterized strongly polynomial algorithm for block structured integer programs"
    - "the complexity landscape of decompositional parameters for ilp"
    - "on the power of tree depth for fully polynomial fpt algorithms"
    - "solving and verifying the boolean pythagorean triples problem via cube and conquer"
    - "kernelizing mso properties of trees of fixed height and some consequences"
    - "a faster parameterized algorithm for treedepth"
    - "structural parameterizations of the mixed chinese postman problem"
    - "where first order and monadic second order logic coincide"

Connected through hyperedge HE-2 (induced by source paper "optimizing tree decompositions in mso"):
  with members:
    - "cutwidth obstructions and algorithmic aspects"
    - "constructive algorithm for path width of matroids"

Connected through hyperedge HE-3 (induced by source paper "a faster parameterized algorithm for treedepth"):
  with members:
    - "a o c k n 5 approximation algorithm for treewidth"
    - "known algorithms on graphs of bounded treewidth are probably optimal"

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)