human: Given a hyperedge-centered hypergraph: <hypergraph>, where the center hyperedge is induced by one source paper and its member nodes are the cited papers.

Details of the hypergraph:
Center hyperedge (induced by source paper "lower bounds for the happy coloring problems"):
  Abstract: In this paper, we study the Maximum Happy Vertices and the Maximum Happy Edges problems (MHV and MHE for short). Very recently, the problems attracted a lot of attention and were studied in Agrawal '18, Aravind et al. '16, Choudhari and Reddy '18, Misra and Reddy '18. Main focus of our work is lower bounds on the computational complexity of these problems. Established lower bounds can be divided into the following groups: NP-hardness of the above guarantee parameterization, kernelization lower bounds (answering questions of Misra and Reddy '18), exponential lower bounds under the Set Cover Conjecture and the Exponential Time Hypothesis, and inapproximability results. Moreover, we present an $\mathcal{O}^*(\ell^k)$ randomized algorithm for MHV and an $\mathcal{O}^*(2^k)$ algorithm for MHE, where $\ell$ is the number of colors used and $k$ is the number of required happy vertices or edges. These algorithms cannot be improved to subexponential taking proved lower bounds into account.

Includes members:
  Member "the parameterized complexity of happy colorings":
    also connected through other hyperedges:
      - Hyperedge HE-1 (induced by source paper "maximizing happiness in graphs of bounded clique width")
  Member "algorithms and hardness results for happy coloring problems":
    also connected through other hyperedges:
      - Hyperedge HE-2 (induced by source paper "maximizing happiness in graphs of bounded clique width")
  Member "on problems as hard as cnf sat":
    also connected through other hyperedges:
      - Hyperedge HE-3 (induced by source paper "coarse grained complexity for dynamic algorithms")
  Member "submodular and supermodular multi labeling and vertex happiness":
    also connected through other hyperedges:
      - Hyperedge HE-4 (induced by source paper "optimizing item and subgroup configurations for social aware vr shopping")
  Member "exponential time complexity of the permanent and the tutte polynomial":
    also connected through other hyperedges:
      - Hyperedge HE-5 (induced by source paper "the fine grained complexity of computing the tutte polynomial of a linear matroid")
  Member "kernelization of packing problems":
    also connected through other hyperedges:
      - Hyperedge HE-6 (induced by source paper "on the approximate compressibility of connected vertex cover")
  Member "quasirandom rumor spreading":
    also connected through other hyperedges:
      - Hyperedge HE-7 (induced by source paper "consensus needs broadcast in noiseless models but can be exponentially easier in the presence of noise")

Question: Please tell me which class the source paper 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)