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: "committees providing ejr can be computed efficiently"
  Abstract: We identify a whole family of approval-based multi-winner voting rules that satisfy PJR. Moreover, we identify a subfamily of voting rules within this family that satisfy EJR. All these voting rules can be computed in polynomial time as long as the subalgorithms that characterize each rule within the family are polynomial. One of the voting rules that satisfy EJR can be computed in $O(n m k^2)$.

Connected through hyperedge HE-1 (induced by source paper "approval based apportionment"):
  with members:
    - "group fairness in committee selection"
    - "fair allocation of indivisible public goods"
    - "monotonicity axioms in approval based multi winner voting rules"
    - "fair mixing the case of dichotomous preferences"
    - "multiwinner approval rules as apportionment methods"
    - "finding a collective set of items from proportional multirepresentation to group recommendation"
    - "justified representation in approval based committee voting"
    - "computational aspects of multi winner approval voting"

Connected through hyperedge HE-2 (induced by source paper "the expanding approvals rule improving proportional representation and monotonicity"):
  with members:
    - "fair knapsack"
    - "a framework for approval based budgeting methods"
    - "the condorcet principle for multiwinner elections from shortlisting to proportionality"
    - "proportionally representative participatory budgeting axioms and algorithms"
    - "monotonicity axioms in approval based multi winner voting rules"
    - "the maximin support method an extension of the d hondt method to approval based multiwinner elections"
    - "computational complexity of testing proportional justified representation"
    - "proportional justified representation"

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)