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: "simultaneous approximation of constraint satisfaction problems"
  Abstract: Given $k$ collections of 2SAT clauses on the same set of variables $V$, can we find one assignment that satisfies a large fraction of clauses from each collection? We consider such simultaneous constraint satisfaction problems, and design the first nontrivial approximation algorithms in this context. #R##N#Our main result is that for every CSP $F$, for $k < \tilde{O}(\log^{1/4} n)$, there is a polynomial time constant factor Pareto approximation algorithm for $k$ simultaneous Max-$F$-CSP instances. Our methods are quite general, and we also use them to give an improved approximation factor for simultaneous Max-w-SAT (for $k <\tilde{O}(\log^{1/3} n)$). In contrast, for $k = \omega(\log n)$, no nonzero approximation factor for $k$ simultaneous Max-$F$-CSP instances can be achieved in polynomial time (assuming the Exponential Time Hypothesis). #R##N#These problems are a natural meeting point for the theory of constraint satisfaction problems and multiobjective optimization. We also suggest a number of interesting directions for future research.

Connected through hyperedge HE-1 (induced by source paper "fair dimensionality reduction and iterative rounding for sdps"):
  with members:
    - "fair and diverse dpp based data summarization"
    - "fair clustering through fairlets"
    - "the price of fair pca one extra dimension"
    - "man is to computer programmer as woman is to homemaker debiasing word embeddings"
    - "discrimination in online ad delivery"
    - "polynomial time computing over quadratic maps i sampling in real algebraic sets"

Connected through hyperedge HE-2 (induced by source paper "democratic fair allocation of indivisible goods"):
  with members:
    - "fairly allocating contiguous blocks of indivisible items"
    - "almost envy freeness in group resource allocation"
    - "connected fair allocation of indivisible goods"
    - "computing a small agreeable set of indivisible items"
    - "comparing approximate relaxations of envy freeness"
    - "fair allocation of combinations of indivisible goods and chores"
    - "almost envy free allocations with connected bundles"
    - "lecture notes on fair division"

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)