human: Given a hyperedge-centered hypergraph: <hypergraph>, where the center hyperedge is induced by one source paper and its member nodes are the cited papers.

Details of the hypergraph:
Center hyperedge (induced by source paper "a ptas for subset tsp in minor free graphs"):
  Abstract: We give the first polynomial time approximation scheme for the subset Traveling Salesperson Problem (subset TSP) in $H$-minor-free graphs. Our main technical contribution is a polynomial time algorithm that, given an edge-weighted $H$-minor-free graph $G$ and a set of $k$ terminals $T$, finds a subgraph of $G$ with weight at most $O_H(\mathrm{poly}(\frac{1}{\epsilon}) \log k)$ times the weight of the minimum Steiner tree for $T$ that preserves pairwise distances between terminals up to $(1+\epsilon)$ factor. This is the first such spanner for $H$-minor-free graphs. Given this spanner, we use the contraction decomposition of Demaine, Hajiaghayi and Kawarabayashi to obtain a PTAS for the subset TSP problem. Our PTAS generalizes PTASes for the same problem by Klein for planar graphs and by Borradaile, Demaine and Tazari for bounded genus graphs.

Includes members:
  Member "truly optimal euclidean spanners":
    also connected through other hyperedges:
      (none)
  Member "greedy spanners are optimal in doubling metrics":
    also connected through other hyperedges:
      - Hyperedge HE-1 (induced by source paper "distributed construction of light networks")
  Member "on subexponential parameterized algorithms for steiner tree and directed subset tsp on planar graphs":
    also connected through other hyperedges:
      - Hyperedge HE-2 (induced by source paper "tight bounds for planar strongly connected steiner subgraph with fixed number of terminals and extensions")
  Member "minor free graphs have light spanners":
    also connected through other hyperedges:
      - Hyperedge HE-3 (induced by source paper "graph spanners a tutorial review")
  Member "the greedy spanner is existentially optimal":
    also connected through other hyperedges:
      - Hyperedge HE-4 (induced by source paper "a polynomial time algorithm for almost optimal vertex fault tolerant spanners")
  Member "linear size distance preservers":
    also connected through other hyperedges:
      - Hyperedge HE-5 (induced by source paper "weighted additive spanners")
  Member "graph minors for preserving terminal distances approximately lower and upper bounds":
    also connected through other hyperedges:
      - Hyperedge HE-6 (induced by source paper "scattering and sparse partitions and their applications")
  Member "a light metric spanner":
    also connected through other hyperedges:
      - Hyperedge HE-7 (induced by source paper "on the edge crossings of the greedy spanner")

Question: Please tell me which class the source paper 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)