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: "improved fpt algorithms for weighted independent set in bull free graphs"
  Abstract: Very recently, Thomass\'e, Trotignon and Vuskovic [WG 2014] have given an FPT algorithm for Weighted Independent Set in bull-free graphs parameterized by the weight of the solution, running in time $2^{O(k^5)} \cdot n^9$. In this article we improve this running time to $2^{O(k^2)} \cdot n^7$. As a byproduct, we also improve the previous Turing-kernel for this problem from $O(k^5)$ to $O(k^2)$. Furthermore, for the subclass of bull-free graphs without holes of length at most $2p-1$ for $p \geq 3$, we speed up the running time to $2^{O(k \cdot k^{\frac{1}{p-1}})} \cdot n^7$. As $p$ grows, this running time is asymptotically tight in terms of $k$, since we prove that for each integer $p \geq 3$, Weighted Independent Set cannot be solved in time $2^{o(k)} \cdot n^{O(1)}$ in the class of $\{bull,C_4,\ldots,C_{2p-1}\}$-free graphs unless the ETH fails.

Connected through hyperedge HE-1 (induced by source paper "when maximum stable set can be solved in fpt time"):
  with members:
    - "maximum independent sets in subcubic graphs new results"
    - "parameterized complexity of independent set in h free graphs"
    - "polynomial time algorithm for maximum weight independent set on p_6 free graphs"
    - "maximum weight independent sets for p_7 triangle free graphs in polynomial time"
    - "deciding first order properties of nowhere dense graphs"

Connected through hyperedge HE-2 (induced by source paper "uniform csp parameterized by solution size is in w 1"):
  with members:
    - "parameterized complexity of csp for infinite constraint languages"
    - "a polynomial turing kernel for weighted independent set in bull free graphs"
    - "losing weight by gaining edges"
    - "constraint satisfaction parameterized by solution size"

Connected through hyperedge HE-3 (induced by source paper "a polynomial turing kernel for weighted independent set in bull free graphs"):
  with members:
    - "turing kernelization for finding long paths and cycles in restricted graph classes"
    - "coloring perfect graphs with no balanced skew partitions"
    - "combinatorial optimization with 2 joins"
    - "maximum weight independent sets in odd hole free graphs without dart or without bull"
    - "on finding directed trees with many leaves"
    - "kernel s for problems with no kernel on out trees with many leaves"

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)