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: "approximating subset k connectivity problems"
  Abstract: A subset $T \subseteq V$ of terminals is $k$-connected to a root $s$ in a directed/undirected graph $J$ if $J$ has $k$ internally-disjoint $vs$-paths for every $v \in T$; $T$ is $k$-connected in $J$ if $T$ is $k$-connected to every $s \in T$. We consider the {\sf Subset $k$-Connectivity Augmentation} problem: given a graph $G=(V,E)$ with edge/node-costs, node subset $T \subseteq V$, and a subgraph $J=(V,E_J)$ of $G$ such that $T$ is $k$-connected in $J$, find a minimum-cost augmenting edge-set $F \subseteq E \setminus E_J$ such that $T$ is $(k+1)$-connected in $J \cup F$. The problem admits trivial ratio $O(|T|^2)$. We consider the case $|T|>k$ and prove that for directed/undirected graphs and edge/node-costs, a $\rho$-approximation for {\sf Rooted Subset $k$-Connectivity Augmentation} implies the following ratios for {\sf Subset $k$-Connectivity Augmentation}: (i) $b(\rho+k) + {(\frac{3|T|}{|T|-k})}^2 H(\frac{3|T|}{|T|-k})$; (ii) $\rho \cdot O(\frac{|T|}{|T|-k} \log k)$, where b=1 for undirected graphs and b=2 for directed graphs, and $H(k)$ is the $k$th harmonic number. The best known values of $\rho$ on undirected graphs are $\min\{|T|,O(k)\}$ for edge-costs and $\min\{|T|,O(k \log |T|)\}$ for node-costs; for directed graphs $\rho=|T|$ for both versions. Our results imply that unless $k=|T|-o(|T|)$, {\sf Subset $k$-Connectivity Augmentation} admits the same ratios as the best known ones for the rooted version. This improves the ratios in \cite{N-focs,L}.

Connected through hyperedge HE-1 (induced by source paper "polylogarithmic approximation algorithm for k connected directed steiner tree on quasi bipartite graphs"):
  with members:
    - "a quasi polynomial algorithm for submodular tree orienteering in directed graphs"
    - "a logarithmic integrality gap bound for directed steiner tree in quasi bipartite graphs"
    - "approximating directed steiner problems via tree embedding"
    - "analytical approach to parallel repetition"
    - "parameters of two prover one round game and the hardness of connectivity problems"
    - "an improved approximation algorithm for the minimum cost subset k connected subgraph problem"
    - "directed steiner tree and the lasserre hierarchy"
    - "an o k 3 log n approximation algorithm for vertex connectivity survivable network design"

Connected through hyperedge HE-2 (induced by source paper "multi level graph sketches via single level solvers"):
  with members:
    - "the sparsest additive spanner via multiple weighted bfs trees"
    - "on pairwise spanners"
    - "label cover instances with large girth and the hardness of approximating basic k spanner"

Connected through hyperedge HE-3 (induced by source paper "approximating k connected m dominating sets"):
  with members:
    - "approximation algorithm for minimum weight fault tolerant virtual backbone in unit disk graphs"
    - "improved approximation algorithms for k connected m dominating set problems"
    - "approximating source location and star survivable network problems"

Connected through hyperedge HE-4 (induced by source paper "improved approximation algorithms for k connected m dominating set problems"):
  with members:
    - "approximation algorithm for minimum weight fault tolerant virtual backbone in unit disk graphs"
    - "constant approximation algorithms for highly connected multi dominating sets in unit disk graphs"
    - "spider covers for prize collecting network activation problem"
    - "parameters of two prover one round game and the hardness of connectivity problems"
    - "an improved approximation algorithm for the minimum cost subset k connected subgraph problem"

Connected through hyperedge HE-5 (induced by source paper "surviving in directed graphs a polylogarithmic approximation for two connected directed steiner tree"):
  with members:
    - "parameters of two prover one round game and the hardness of connectivity problems"
    - "iterative rounding approximation algorithms for degree bounded node connectivity network design"
    - "approximating minimum cost k node connected subgraphs via independence free graphs"
    - "an improved approximation algorithm for the minimum cost subset k connected subgraph problem"
    - "directed steiner tree and the lasserre hierarchy"

Connected through hyperedge HE-6 (induced by source paper "spider covers for prize collecting network activation problem"):
  with members:
    - "covering problems in edge and node weighted graphs"
    - "improved approximation algorithms for budgeted node weighted steiner problems"
    - "an lmp o log n approximation algorithm for node weighted prize collecting steiner tree"
    - "an o k 3 log n approximation algorithm for vertex connectivity survivable network design"

Connected through hyperedge HE-7 (induced by source paper "iterative rounding approximation algorithms for degree bounded node connectivity network design"):
  with members:
    - "approximating minimum cost edge covers of crossing biset families"
    - "approximating minimum cost k node connected subgraphs via independence free graphs"
    - "on generalizations of network design problems with degree bounds"
    - "improved algorithm for degree bounded survivable network design problem"
    - "an o k 3 log n approximation algorithm for vertex connectivity survivable network design"

Connected through hyperedge HE-8 (induced by source paper "approximating minimum cost edge covers of crossing biset families"):
  with members:
    - "iterative rounding approximation algorithms for degree bounded node connectivity network design"
    - "approximating minimum cost k node connected subgraphs via independence free graphs"

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)