Dispersion on Trees

Authors Pawel Gawrychowski, Nadav Krasnopolsky, Shay Mozes, Oren Weimann



PDF
Thumbnail PDF

File

LIPIcs.ESA.2017.40.pdf
  • Filesize: 476 kB
  • 13 pages

Document Identifiers

Author Details

Pawel Gawrychowski
Nadav Krasnopolsky
Shay Mozes
Oren Weimann

Cite As Get BibTex

Pawel Gawrychowski, Nadav Krasnopolsky, Shay Mozes, and Oren Weimann. Dispersion on Trees. In 25th Annual European Symposium on Algorithms (ESA 2017). Leibniz International Proceedings in Informatics (LIPIcs), Volume 87, pp. 40:1-40:13, Schloss Dagstuhl – Leibniz-Zentrum für Informatik (2017) https://doi.org/10.4230/LIPIcs.ESA.2017.40

Abstract

In the k-dispersion problem, we need to select k nodes of a given graph so as to maximize the minimum distance between any two chosen nodes. This can be seen as a generalization of the independent set problem, where the goal is to select nodes so that the minimum distance is larger than 1. We design an optimal O(n) time algorithm for the dispersion problem on trees consisting of n nodes, thus improving the previous  O(n log n) time solution from 1997. 

We also consider the weighted case, where the goal is to choose a set of nodes of total weight at least W. We present an O(n log^2n) algorithm improving the previous O(n log^4 n) solution. Our solution builds on the search version (where we know the minimum distance lambda between the chosen nodes) for which we present tight Theta(n log n) upper and lower bounds.

Subject Classification

Keywords
  • parametric search
  • dispersion
  • k-center
  • dynamic programming

Metrics

  • Access Statistics
  • Total Accesses (updated on a weekly basis)
    0
    PDF Downloads

References

  1. R.I. Becker, S.R. Schach, and Y. Perl. A shifting algorithm for min-max tree partitioning. J. ACM, 29(1):56-67, 1982. Google Scholar
  2. B.K. Bhattacharya and M.E. Houle. Generalized maximum independent sets for trees. In CATS, pages 17-25, 1997. Google Scholar
  3. B.K. Bhattacharya and M.E. Houle. Generalized maximum independent sets for trees in subquadratic time. In ISAAC, pages 435-445, 1999. Google Scholar
  4. M.R. Brown and R.E. Tarjan. Design and analysis of a data structure for representing sorted lists. SIAM Journal on Computing, 9(3):594-614, 1980. Google Scholar
  5. Richard Cole. Slowing down sorting networks to obtain faster sorting algorithms. J. ACM, 34(1):200-208, 1987. Google Scholar
  6. G.N. Frederickson. Optimal algorithms for partitioning trees and locating p-centers in trees. Technical Report CSD-TR-1029, Purdue University, 1990. Google Scholar
  7. G.N. Frederickson. Optimal algorithms for tree partitioning. In SODA, pages 168-177, 1991. Google Scholar
  8. G.N. Frederickson. Parametric search and locating supply centers in trees. In WADS, pages 299-319, 1991. Google Scholar
  9. G.N. Frederickson and D.B. Johnson. Finding k-th paths and p-centers by generating and searching good data structures. J. Algorithms, 4(1):61-80, 1983. Google Scholar
  10. Scott Huddleston and Kurt Mehlhorn. A new data structure for representing sorted lists. Acta Inf., 17:157-184, 1982. Google Scholar
  11. N. Megiddo and A. Tamir. New results on the complexity of p-center problems. SIAM J. Computing, 12(3):751-758, 1983. Google Scholar
  12. N. Megiddo, A. Tamir, E. Zemel, and R. Chandrasekaran. An O(n log² n) algorithm for the k-th longest path in a tree with applications to location problems. SIAM J. Computing, 10(2):328-337, 1981. Google Scholar
  13. Y. Perl and S.R. Schach. Max-min tree partitioning. J. ACM, 28(1):5-15, 1981. Google Scholar
  14. D.B. Shmoys, É. Tardos, and K. Aardal. Approximation algorithms for facility location problems. In STOC, pages 265-274, 1997. Google Scholar
  15. D.D. Sleator and R.E. Tarjan. A data structure for dynamic trees. Journal of Computer and System Sciences, 26(3):362–391, 1983. Google Scholar
  16. V.V. Vazirani. Approximation Algorithms. Springer, 2003. Google Scholar
Questions / Remarks / Feedback
X

Feedback for Dagstuhl Publishing


Thanks for your feedback!

Feedback submitted

Could not send message

Please try again later or send an E-mail