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: "binary pattern tile set synthesis is np hard"
  Abstract: In the field of algorithmic self-assembly, a long-standing unproven conjecture has been that of the NP-hardness of binary pattern tile set synthesis (2-PATS). The $k$-PATS problem is that of designing a tile assembly system with the smallest number of tile types which will self-assemble an input pattern of $k$ colors. Of both theoretical and practical significance, $k$-PATS has been studied in a series of papers which have shown $k$-PATS to be NP-hard for $k = 60$, $k = 29$, and then $k = 11$. In this paper, we close the fundamental conjecture that 2-PATS is NP-hard, concluding this line of study. #R##N#While most of our proof relies on standard mathematical proof techniques, one crucial lemma makes use of a computer-assisted proof, which is a relatively novel but increasingly utilized paradigm for deriving proofs for complex mathematical problems. This tool is especially powerful for attacking combinatorial problems, as exemplified by the proof of the four color theorem by Appel and Haken (simplified later by Robertson, Sanders, Seymour, and Thomas) or the recent important advance on the Erd\H{o}s discrepancy problem by Konev and Lisitsa using computer programs. We utilize a massively parallel algorithm and thus turn an otherwise intractable portion of our proof into a program which requires approximately a year of computation time, bringing the use of computer-assisted proofs to a new scale. We fully detail the algorithm employed by our code, and make the code freely available online.

Connected through hyperedge HE-1 (induced by source paper "the complexity of fixed height patterned tile self assembly"):
  with members:
    - "combinatorial optimization in pattern assembly"
    - "intrinsic universality and the computational power of self assembly"
    - "synthesizing minimal tile sets for patterned dna self assembly"

Connected through hyperedge HE-2 (induced by source paper "noncooperative algorithms in self assembly"):
  with members:
    - "the two handed tile assembly model is not intrinsically universal"
    - "intrinsic universality in tile self assembly requires cooperation"
    - "tiling problems on baumslag solitar groups"
    - "one tile to rule them all simulating any turing machine tile assembly system or tiling system with a single puzzle piece"
    - "the tile assembly model is intrinsically universal"
    - "intrinsic universality in self assembly"
    - "temperature 1 self assembly deterministic assembly in 3d and probabilistic assembly in 2d"
    - "limitations of self assembly at temperature one extended abstract"

Connected through hyperedge HE-3 (induced by source paper "reflections on tiles in self assembly"):
  with members:
    - "universal computation with arbitrary polyomino tiles in non cooperative self assembly"
    - "the power of duples in self assembly it s not so hip to be square"
    - "optimizing tile concentrations to minimize errors and time for dna tile self assembly systems"
    - "one tile to rule them all simulating any turing machine tile assembly system or tiling system with a single puzzle piece"
    - "self assembly with geometric tiles"
    - "negative interactions in irreversible self assembly"
    - "strict self assembly of discrete sierpinski triangles"
    - "temperature 1 self assembly deterministic assembly in 3d and probabilistic assembly in 2d"

Connected through hyperedge HE-4 (induced by source paper "a manually checkable proof for the np hardness of 11 color pattern self assembly tile set synthesis"):
  with members:
    - "search methods for tile sets in patterned dna self assembly"
    - "3 color bounded patterned self assembly"

Connected through hyperedge HE-5 (induced by source paper "3 color bounded patterned self assembly"):
  with members:
    - "combinatorial optimization in pattern assembly"
    - "synthesizing minimal tile sets for patterned dna self assembly"

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.CC(Computational Complexity)