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: "on column restricted and priority covering integer programs"
  Abstract: In a column-restricted covering integer program (CCIP), all the non-zero entries of any column of the constraint matrix are equal. Such programs capture capacitated versions of covering problems. In this paper, we study the approximability of CCIPs, in particular, their relation to the integrality gaps of the underlying 0,1-CIP. #R##N#If the underlying 0,1-CIP has an integrality gap O(gamma), and assuming that the integrality gap of the priority version of the 0,1-CIP is O(omega), we give a factor O(gamma + omega) approximation algorithm for the CCIP. Priority versions of 0,1-CIPs (PCIPs) naturally capture quality of service type constraints in a covering problem. #R##N#We investigate priority versions of the line (PLC) and the (rooted) tree cover (PTC) problems. Apart from being natural objects to study, these problems fall in a class of fundamental geometric covering problems. We bound the integrality of certain classes of this PCIP by a constant. Algorithmically, we give a polytime exact algorithm for PLC, show that the PTC problem is APX-hard, and give a factor 2-approximation algorithm for it.

Connected through hyperedge HE-1 (induced by source paper "geometry of scheduling on multiple machines"):
  with members:
    - "scheduling to approximate minimization objectives on identical machines"
    - "a polynomial time constant approximation for minimizing total weighted flow time"
    - "a primal dual approximation algorithm for min sum single machine scheduling problems"
    - "how unsplittable flow covering helps scheduling with job dependent cost functions"
    - "the geometry of scheduling"

Connected through hyperedge HE-2 (induced by source paper "constant factor approximation algorithm for weighted flow time on a single machine in pseudo polynomial time"):
  with members:
    - "the geometry of scheduling"

Connected through hyperedge HE-3 (induced by source paper "approximate deadline scheduling with precedence constraints"):
  with members:
    - "approximation algorithms for covering packing integer programs"

Connected through hyperedge HE-4 (induced by source paper "sum of squares hierarchy lower bounds for symmetric formulations"):
  with members:
    - "tight sum of squares lower bounds for binary polynomial optimization problems"
    - "on the sum of squares degree of symmetric quadratic functions"
    - "on the hardest problem formulations for the 0 1 lasserre hierarchy"
    - "a lasserre lower bound for the min sum single machine scheduling problem"
    - "sum of squares lower bounds from pairwise independence"
    - "sum of squares lower bounds for planted clique"
    - "a 4 approximation for scheduling on a single machine with general cost function"
    - "lower bounds on the size of semidefinite programming relaxations"

Connected through hyperedge HE-5 (induced by source paper "the lasserre hierarchy in almost diagonal form"):
  with members:
    - "rounding sum of squares relaxations"
    - "hypercontractivity sum of squares proofs and their applications"
    - "approximability and proof complexity"
    - "polynomial integrality gaps for strong sdp relaxations of densest k subgraph"
    - "approximating csps with global cardinality constraints using sdp hierarchies"
    - "the geometry of scheduling"

Connected through hyperedge HE-6 (induced by source paper "distributed and parallel algorithms for set cover problems with small neighborhood covers"):
  with members:
    - "a new multilayered pcp and the hardness of hypergraph vertex cover"
    - "a primal dual parallel approximation technique applied to weighted set and vertex covers"

Connected through hyperedge HE-7 (induced by source paper "approximating sparse covering integer programs online"):
  with members:
    - "approximability of sparse integer programs"
    - "on k column sparse packing programs"
    - "approximation algorithms for covering packing integer programs"
    - "the k server dual and loose competitiveness for paging"

Connected through hyperedge HE-8 (induced by source paper "an lp with integrality gap 1 epsilon for multidimensional knapsack"):
  with members:
    - "approximability of capacitated network design"
    - "integrality gaps of linear and semi definite programming relaxations for knapsack"
    - "approximability of sparse integer programs"
    - "dependent randomized rounding for matroid polytopes and applications"

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.DS(Data Structures and Algorithms)