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: "new algorithms for unordered tree inclusion"
  Abstract: The tree inclusion problem is, given two node-labeled trees $P$ and $T$ (the "pattern tree" and the "text tree"), to locate every minimal subtree in $T$ (if any) that can be obtained by applying a sequence of node insertion operations to $P$. The ordered tree inclusion problem is known to be solvable in polynomial time while the unordered tree inclusion problem is NP-hard. The currently fastest algorithm for the latter is from 1995 and runs in $O(poly(m,n) \cdot 2^{2d}) = O^{\ast}(4^{d})$ time, where $m$ and $n$ are the sizes of the pattern and text trees, respectively, and $d$ is the degree of the pattern tree. Here, we develop a new algorithm that improves the exponent $2d$ to $d$ by considering a particular type of ancestor-descendant relationships and applying dynamic programming, thus reducing the time complexity to $O^{\ast}(2^{d})$. We then study restricted variants of the unordered tree inclusion problem where the number of occurrences of different node labels and/or the input trees' heights are bounded and show that although the problem remains NP-hard in many such cases, if the leaves of $P$ are distinctly labeled and each label occurs at most $c$ times in $T$ then it can be solved in polynomial time for $c = 2$ and in $O^{\ast}(1.8^d)$ time for $c = 3$.

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)