Skip to main content

Implementation of Approximation Algorithms for Weighted and Unweighted Edge-Disjoint Paths in Bidirected Trees

  • Conference paper
  • First Online:
Book cover Algorithm Engineering (WAE 2000)

Part of the book series: Lecture Notes in Computer Science ((LNCS,volume 1982))

Included in the following conference series:

  • 419 Accesses

Abstract

Given a set of weighted directed paths in a bidirected tree, the maximum weight edge-disjoint paths problem (MWEDP) is to select a subset of the given paths such that the selected paths are edge-disjoint and the total weight of the selected paths is maximized. MWEDP is NPhard for bidirected trees of arbitrary degree, even if all weights are the same (the unweighted case). Three different approximation algorithms are implemented: a known combinatorial ( 5/3+ε)-approximation algorithm A1 for the unweighted case, a new combinatorial 2-approximation algorithm A2 for the weighted case, and a known ( 5/3 +ε)-approximation algorithm A3 for the weighted case that is based on linear programming. For algorithm A1, it is shown how efficient data structures can be used to obtain a worst-case running-time of O(m+n+41/ε √ n.m) for instances consisting of m paths in a tree with n nodes. Experimental results regarding the running-times and the quality of the solutions obtained by the three approximation algorithms are reported. Where possible, the approximate solutions are compared to the optimal solutions, which were computed by running CPLEX on an integer linear programming formulation of MWEDP.

This is a preview of subscription content, log in via an institution to check access.

Access this chapter

Chapter
USD 29.95
Price excludes VAT (USA)
  • Available as PDF
  • Read on any device
  • Instant download
  • Own it forever
eBook
USD 39.99
Price excludes VAT (USA)
  • Available as PDF
  • Read on any device
  • Instant download
  • Own it forever
Softcover Book
USD 54.99
Price excludes VAT (USA)
  • Compact, lightweight edition
  • Dispatched in 3 to 5 business days
  • Free shipping worldwide - see info

Tax calculation will be finalised at checkout

Purchases are for personal use only

Institutional subscriptions

Preview

Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

References

  1. A. Bar-Noy, R. Bar-Yehuda, A. Freund, J. S. Naor, and B. Schieber. A unified approach to approximating resource allocation and scheduling. In Proceedings of the 32nd Annual ACM Symposium on Theory of Computing STOC’00, pages 735–744, 2000.

    Google Scholar 

  2. A. Bar-Noy, S. Guha, J. S. Naor, and B. Schieber. Approximating the throughput of multiple machines under real-time scheduling. In Proceedings of the 31st Annual ACM Symposium on Theory of Computing STOC’99, pages 622–631, 1999.

    Google Scholar 

  3. P. Berman and B. DasGupta. Improvements in throughput maximization for realtime scheduling. In Proceedings of the 32nd Annual ACM Symposium on Theory of Computing STOC’00, pages 680–687, 2000.

    Google Scholar 

  4. T. Erlebach. Scheduling Connections in Fast Networks. PhD thesis, Technische Universität München, 1999.http://www.tik.ee.ethz.ch/?erlebach/dissertation.ps.gz.

  5. T. Erlebach and K. Jansen. Efficient implementation of an optimal greedy algorithm for wavelength assignment in directed tree networks. In K. Mehlhorn, editor, Proceedings of the 2nd Workshop on Algorithm Engineering WAE’98, Technical Report MPI-I-98-1-019, pages 13–24, Max-Planck-Institut für Informatik, Saarbrücken, August 1998.

    Google Scholar 

  6. T. Erlebach and K. Jansen. Maximizing the number of connections in optical tree networks. In Proceedings of the 9th Annual International Symposium on Algorithms and Computation ISAAC’98, LNCS 1533, pages 179–188, 1998.

    Google Scholar 

  7. T. Erlebach and K. Jansen. Conversion of coloring algorithms into maximum weight independent set algorithms. In ICALP Workshops 2000, Proceedings in Informatics 8, pages 135–145. Carleton Scientific, 2000.

    Google Scholar 

  8. T. Erlebach, K. Jansen, C. Kaklamanis, M. Mihail, and P. Persiano. Optimal wavelength routing on directed fiber trees. Theoretical Computer Science, 221:119–137, 1999. Special issue of ICALP’97.

    Article  MathSciNet  Google Scholar 

  9. T. Erlebach, K. Jansen, C. Kaklamanis, and P. Persiano. An optimal greedy algorithm for wavelength allocation in directed tree networks. In Proceedings of the DIMACS Workshop on Network Design: Connectivity and Facilities Location, volume 40of DIMACS Series in Discrete Mathematics and Theoretical Computer Science, pages 117–129. AMS, 1998.

    Google Scholar 

  10. N. Garg, V. V. Vazirani, and M. Yannakakis. Primal-dual approximation algorithms for integral flow and multicut in trees, with applications to matching and set cover. In Proceedings of the 20th International Colloquium on Automata, Languages and Programming ICALP’93, LNCS 700, pages 64–75, 1993.

    MATH  Google Scholar 

  11. J. Hopcroft and R. Karp. An n5/2 algorithm for maximum matchings in bipartite graphs. SIAM J. Comput., 2(4):225–231, 1973.

    Article  MathSciNet  Google Scholar 

  12. K. Mehlhorn and S. Näher. LEDA — A Platform for Combinatorial and Geometrical Computing. Cambridge University Press, 1999.

    Google Scholar 

  13. B. Schieber and U. Vishkin. On finding lowest common ancestors: Simplification and parallelization. SIAM J. Comput., 17:1253–1262, 1988.

    Article  MathSciNet  Google Scholar 

Download references

Author information

Authors and Affiliations

Authors

Editor information

Editors and Affiliations

Rights and permissions

Reprints and permissions

Copyright information

© 2001 Springer-Verlag Berlin Heidelberg

About this paper

Cite this paper

Erlebach, T., Jansen, K. (2001). Implementation of Approximation Algorithms for Weighted and Unweighted Edge-Disjoint Paths in Bidirected Trees. In: Näher, S., Wagner, D. (eds) Algorithm Engineering. WAE 2000. Lecture Notes in Computer Science, vol 1982. Springer, Berlin, Heidelberg. https://doi.org/10.1007/3-540-44691-5_17

Download citation

  • DOI: https://doi.org/10.1007/3-540-44691-5_17

  • Published:

  • Publisher Name: Springer, Berlin, Heidelberg

  • Print ISBN: 978-3-540-42512-0

  • Online ISBN: 978-3-540-44691-0

  • eBook Packages: Springer Book Archive

Publish with us

Policies and ethics