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: "hardness of mastermind"
  Abstract: Mastermind is a popular board game released in 1971, where a codemaker chooses a secret pattern of colored pegs, and a codebreaker has to guess it in several trials. After each attempt, the codebreaker gets a response from the codemaker containing some information on the number of correctly guessed pegs. The search space is thus reduced at each turn, and the game continues until the codebreaker is able to find the correct code, or runs out of trials. #R##N#In this paper we study several variations of #MSP, the problem of computing the size of the search space resulting from a given (possibly fictitious) sequence of guesses and responses. Our main contribution is a proof of the #P-completeness of #MSP under parsimonious reductions, which settles an open problem posed by Stuckman and Zhang in 2005, concerning the complexity of deciding if the secret code is uniquely determined by the previous guesses and responses. Similarly, #MSP stays #P-complete under Turing reductions even with the promise that the search space has at least k elements, for any constant k. (In a regular game of Mastermind, k=1.) #R##N#All our hardness results hold even in the most restrictive setting, in which there are only two available peg colors, and also if the codemaker's responses contain less information, for instance like in the so-called single-count (black peg) Mastermind variation.

Connected through hyperedge HE-1 (induced by source paper "on the query complexity of black peg ab mastermind"):
  with members:
    - "the worst case number of questions in generalized ab game with and without white peg answers"
    - "improved approximation algorithm for the number of queries necessary to identify a permutation"
    - "playing mastermind with many colors"
    - "playing mastermind with constant size memory"
    - "on the algorithmic complexity of the mastermind game with black peg results"
    - "the mastermind attack on genomic data"
    - "mastermind is np complete"

Connected through hyperedge HE-2 (induced by source paper "the worst case number of questions in generalized ab game with and without white peg answers"):
  with members:
    - "improved approximation algorithm for the number of queries necessary to identify a permutation"
    - "playing mastermind with many colors"
    - "playing mastermind with constant size memory"
    - "on the algorithmic complexity of the mastermind game with black peg results"
    - "mastermind is np complete"

Connected through hyperedge HE-3 (induced by source paper "improved approximation algorithm for the number of queries necessary to identify a permutation"):
  with members:
    - "playing mastermind with many colors"
    - "playing mastermind with constant size memory"
    - "on the algorithmic complexity of the mastermind game with black peg results"
    - "mastermind is np complete"

Connected through hyperedge HE-4 (induced by source paper "playing mastermind with many colors"):
  with members:
    - "playing mastermind with constant size memory"
    - "on the algorithmic complexity of the mastermind game with black peg results"
    - "the mastermind attack on genomic data"
    - "a constructive proof of the lovasz local lemma"
    - "mastermind is np complete"

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.GT(Computer Science and Game Theory)