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 lower bounds for the maximum number of runs in a string"
  Abstract: We show a new lower bound for the maximum number of runs in a string. We prove that for any e > 0, (a -- e)n is an asymptotic lower bound, where a = 56733/60064 = 0.944542. It is superior to the previous bound 0.927 given by Franek et al. Moreover, our construction of the strings and the proof is much simpler than theirs.

Connected through hyperedge HE-1 (induced by source paper "the runs theorem"):
  with members:
    - "computing runs on a general alphabet"
    - "internal pattern matching queries in a text and applications"
    - "lyndon words and short superstrings"
    - "on the maximal sum of exponents of runs in a string"
    - "on bijective variants of the burrows wheeler transform"
    - "circle formation of weak robots and lyndon words"

Connected through hyperedge HE-2 (induced by source paper "beyond the runs theorem"):
  with members:
    - "the runs theorem"

Connected through hyperedge HE-3 (induced by source paper "self index based on lz77"):
  with members:
    - "optimal succinctness for range minimum queries"
    - "practical entropy compressed rank select dictionary"

Connected through hyperedge HE-4 (induced by source paper "on the maximal number of highly periodic runs in a string"):
  with members:
    - "on the maximal number of cubic subwords in a string"

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)