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On defect sets in bipartite graphs (extended abstract)

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Algorithms and Computation (ISAAC 1997)

Part of the book series: Lecture Notes in Computer Science ((LNCS,volume 1350))

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Abstract

A defect set in a bipartite graph with vertex classes V and W is a subset XV such that the neighbourhood N(X) satisfies |N(X)| < |X|. We study a lemma on defect sets in bipartite graphs with certain expanding properties from the algorithmic complexity point of view. This lemma is the core of a result of Friedman and Pippenger which states that expanding graphs contain all small trees. We also discuss related problems of finding shortest circuits of matroids represented over a field. In particular, we propose a new straightforward method to derive a weaker form (PR-completeness) of the recent NP-completeness results of Khachiyan [11] and Vardy [18] concerning this problem for the field of rationals and GF(p m), respectively.

The first author was partially supported by NSERC.

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References

  1. A. Aggarwal, A. Bar-noy, D. Coppersmith, R. Ramaswami, B. Schieber, M. Sudan, Efficient Routing and Scheduling Algorithms for Optical Networks, in Proceedings of the Fifth Annual ACM-SIAM Symposium on Discrete Algorithms, Philadelphia, Pennsylvania, 23–25 January 1994, pp. 412–423.

    Google Scholar 

  2. M. Ajtai, Generating Hard Instances of Lattice Problems, preprint 1996.

    Google Scholar 

  3. I. Barany, S. Onn, Colourful Linear Programming And its Relatives, Mathematics of Operations Research, to appear.

    Google Scholar 

  4. E.R. Berlekamp, R. McEliece, H. van Tilborg, On the Inherent Intractability of Certain Coding Problems, IEEE Transactions on Information Theory 24 (1978), pp.384–386.

    Google Scholar 

  5. M. Blum, R.M. Karp, O. Vornberger, C.H. Papadimitriou, M. Yannakakis, The Complexity of Testing Whether a Graph Is a Superconcentrator, Information Processing Letters 13 (1981), pp. 164–167.

    Google Scholar 

  6. P. Feldman, J. Friedman, N. Pippenger, Wide-Sense Nonblocking Networks, SIAM J. Disc. Math. 1 (1988), pp. 158–173.

    Google Scholar 

  7. J. Friedman, N. Pippenger, Expanding Graphs Contain All Small Trees, Combinatorica 7 (1) (1987), pp.71–76.

    Google Scholar 

  8. P.E. Haxell, Y. Kohayakawa, The Size-Ramsey Number of Trees, Israel J. of Mathematics 89 (1995), pp. 261–274.

    Google Scholar 

  9. D.S. Johnson, The NP-Completeness Column: An Ongoing Guide, J. of Algorithms 5 (1984), pp. 433–447.

    Google Scholar 

  10. D.S. Johnson, A Catalog of Complexity Classes, in Handbook of Theoretical Computer Science, Vol. A (J. Van Leeuwen, ed.), Elsevier 1990, pp. 67–162.

    Google Scholar 

  11. L. Khachiyan, On the Complexity of Approximating Extremal Determinants in Matrices, J. of Complexity 11 (1995), pp.138–153.

    Google Scholar 

  12. J. Oxley, Matroid Theory, Oxford University Press, 1992.

    Google Scholar 

  13. C.H. Papadimitriou, M. Yannakakis, The Complexity of Facets (And Some Facets of Complexity), J. Comput. System Sci. 28 (1984), pp.244–259.

    Google Scholar 

  14. M.J. Piff, D.J.A. Welsh, On the vector representation of matroids, J. London Math. Soc. (2) 2, pp. 284–288.

    Google Scholar 

  15. A. Schrijver, Theory of Integer and Linear Programming, Wiley, Chichester, 1986.

    Google Scholar 

  16. J.T. Schwartz, Fast Probabilistic Algorithms For Verification of Polynomial Identities, Journal of the ACM 27 (1980), pp.701–717.

    Google Scholar 

  17. L.G. Valiant, V. Vazirani, NP Is As Easy As Detecting Unique Solutions, Theoretical Computer Science 47 (1986), pp.85–93.

    Google Scholar 

  18. A. Vardy, The Intractability of Computing the Minimum Distance of a Code, manuscript November 1996.

    Google Scholar 

  19. U.V. Vazirani, V.V. Vazirani, A Natural Encoding Scheme Proved Probabilistic Polynomial Complete, Theoretical Computer Science 24 (1983), pp. 291–300.

    Google Scholar 

  20. D.J.A. Welsh, Complexity: Knots, Colourings and Counting, Cambridge University Press, 1993.

    Google Scholar 

  21. R.E. Zippel, Probabilistic Algorithms for Sparse Polynomials, In Proceedings of EUROSAM 79, volume 72 of Lecture Notes in Computer Science, (1979), pp. 216–226.

    Google Scholar 

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Hon Wai Leong Hiroshi Imai Sanjay Jain

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© 1997 Springer-Verlag Berlin Heidelberg

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Haxell, P.E., Loebl, M. (1997). On defect sets in bipartite graphs (extended abstract). In: Leong, H.W., Imai, H., Jain, S. (eds) Algorithms and Computation. ISAAC 1997. Lecture Notes in Computer Science, vol 1350. Springer, Berlin, Heidelberg. https://doi.org/10.1007/3-540-63890-3_36

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  • DOI: https://doi.org/10.1007/3-540-63890-3_36

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