Improved Algorithms for Computing k-Sink on Dynamic Flow Path Networks

  • Binay Bhattacharya
  • Mordecai J. Golin
  • Yuya Higashikawa
  • Tsunehiko Kameda
  • Naoki Katoh
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 10389)

Abstract

We address the problem of locating k sinks on dynamic flow path networks with n vertices in such a way that the evacuation completion time to them is minimized. Our two algorithms run in \(O(n\log n + k^2\log ^4 n)\) and \(O(n\log ^3 n)\) time, respectively. When all edges have the same capacity, we also present two algorithms which run in \(O(n + k^2\log ^2n)\) time and \(O(n\log n)\) time, respectively. These algorithms together improve upon the previously most efficient algorithms, which have time complexities \(O(kn\log ^2n)\) [1] and O(kn) [11], in the general and uniform edge capacity cases, respectively. The above results are achieved by organizing relevant data for subpaths in a strategic way during preprocessing, and the final results are obtained by extracting/merging them in an efficient manner.

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Copyright information

© Springer International Publishing AG 2017

Authors and Affiliations

  • Binay Bhattacharya
    • 1
  • Mordecai J. Golin
    • 2
  • Yuya Higashikawa
    • 3
  • Tsunehiko Kameda
    • 1
  • Naoki Katoh
    • 4
  1. 1.School of Computing ScienceSimon Fraser UniversityBurnabyCanada
  2. 2.Dept. of Computer ScienceHong Kong Univ. of Science and TechnologyHong KongChina
  3. 3.Dept. of Information and System EngineeringChuo UniversityTokyoJapan
  4. 4.School of Science and TechnologyKwansei Gakuin UniversityHyogoJapan

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