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: "unit length embedding of cycles and paths on grid graphs"
  Abstract: AbstractAlthough there are veryalgorithms for embeddinggraphs on unboundedgrids, only few results on embedding or drawing graphs on restricted gridshas been published. In this work, we consider the problem of embeddingpaths and cycles on grid graphs. We give the necessary and suﬃcientconditions for the existence of cycles of given length kand paths of givenlength k between two given vertices in n-vertex rectangular grid graphsand introduce two algorithms with running times O(k) and O(k 2 ) forﬁnding respectively such cycles and paths. Also, we extend our results tom×n×o3D grids. Our method for ﬁnding cycle of length kin rectangulargrid graphs also introduces a linear-time algorithm for ﬁnding cycles of agiven length kin hamiltonian solid grid graphs.Keywords:Grid graphs, Rectangular grid graphs, 3D grids, Hamilto-nian path, Hamiltonian cycle, Longest Path. 1 Introduction In the area of graph drawing, a lot of research has been done on drawingor embedding various classes of graphs on grids. Most of the research thusfar, has considered unbounded grids, and in some cases tried to minimizethe area used for drawing the given graph, and only a few results dealwith drawing or embedding graphs on restricted grids. Felsner et al. [6]considered the problem of drawing graphs on k-tracks, i.e. ∞ × k grids.They characterized the 2-track drawable trees and devised a linear-timealgorithm for constructing such drawings. Cornelsen et al. [3] proposeda polynomial-time algorithm for planar drawing of an arbitrary graph ontwo parallel lines. Their results show that, only outer planar graphs may

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.DM(Discrete Mathematics)