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: "state complexes for metamorphic robots"
  Abstract: A metamorphic robotic system is an aggregate of homogeneous robot units which can individually and selectively locomote in such a way as to change the global shape of the system. We introduce a mathematical framework for defining and analyzing general metamorphic robots. This formal structure, combined with ideas from geometric group theory, leads to a natural extension of a configuration space for metamorphic robots -- the state complex -- which is especially adapted to parallelization. We present an algorithm for optimizing reconfiguration sequences with respect to elapsed time. A universal geometric property of state complexes -- non-positive curvature -- is the key to proving convergence to the globally time-optimal solution.

Connected through hyperedge HE-1 (induced by source paper "distance and routing labeling schemes for cube free median graphs"):
  with members:
    - "on density of subgraphs of cartesian products"
    - "a polynomial time algorithm to compute geodesics in cat 0 cubical complexes"
    - "a counterexample to thiagarajan s conjecture on regular event structures"
    - "a note on distance labeling in planar graphs"
    - "simpler faster and shorter labels for distances in graphs"
    - "sublinear distance labeling"
    - "distance labeling schemes for trees"
    - "shortest path problem in rectangular complexes of global nonpositive curvature"

Connected through hyperedge HE-2 (induced by source paper "a polynomial time algorithm to compute geodesics in cat 0 cubical complexes"):
  with members:
    - "shortest path problem in rectangular complexes of global nonpositive curvature"

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.RO(Robotics)