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Finding the ith largest of n for small i,n

Authors:

William Gasarch,

William PughAuthors Info & Claims

ACM SIGACT News, Volume 27, Issue 2

Pages 88 - 96

https://doi.org/10.1145/235767.235772

Published: 01 July 1996 Publication History

Abstract

A classic problem in computer science is selection: given a list of n numbers, find the ith largest, using the fewest number of comparisons. We are interested in the exact number of comparisons required for specific small values of i and n. We have written a program that can be used either to find the exact number of comparisons for very low values of i and n, or to find upper bounds on the number of comparisons for slightly larger values of i and n. In some cases we have improved on the results in the literature and have additional improvements contingent on a conjecture.

References

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{1} S. Bent and J. John. Finding the median requires 2n comparisons. In Proc. of the 17th ACM Sym. on Theory of Computing, 1985.

Digital Library

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{2} M. Blum, R. W. Floyd, V. R. Pratt, R. L. Rivest, and R. E. Tarjan. Time bounds for selection. J. Comput. Syat. Sci., 7:448-461, 1973.

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{3} D. Dor. Selection Algorithms. PhD thesis, Tel-Aviv University, 1995.

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{4} D. Dor and U. Zwick. Selecting the median. In Proc. 6th Annual Sym. on Discrete Algorithms, 1995.

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{5} F. Fussenegger and H. Gabow. A counting approach to lower bounds for selection problems. J. ACM, 26(2):227-238, April 1979.

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{6} J. W. John. The Complexity of Selection Problems. PhD thesis, The University of Wisconsin at Madison, 1985.

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{7} J. W. John. A new lower bound for the set-partitioning problem. SIAM J. Comput., 17(4):640- 647, Aug. 1988.

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{8} D. Kirkpatrick. A unified lower bound for selection and set partitioning problems. J. ACM, 39, 1981.

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{9} D. E. Knuth. Sorting and Searching, volume 3 of The Art of Computer Programming. Addison-Wesley, Reading, MA, 1973.

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{10} A. Newell, J. Shaw, and H. Simon. Efficient randomized pattern-matching algorithms. IBM Journal of Res. and Dev., pages 320-355, 1958.

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{11} N. J. Nilsson. Principles of Artificial Intelligence. Morgan Kaufmann Publishers, 1980.

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{12} V. Pratt and F. F. Yao. On lower bounds for computing the i-th largest element. In Proc. of the 14th IEEE Sym. on Found. of Comp. Sci., pages 70-81, 1973.

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{13} Schoenhage, Paterson, and Pippenger. Finding the median. J. Comput. Syst. Sci., 13, 1976.

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{14} C. Shannon. Programming a computer for playing chess. Philosophical Magazine, 41:256-275, 1950.

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{15} T. Spencer, 1992. Personal communication.

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{16} U. Zwick, February 1996. Personal communication.

Cited By

Chen KDumitrescu A(2020)Selection Algorithms with Small GroupsInternational Journal of Foundations of Computer Science10.1142/S012905412050013631:03(355-369)Online publication date: 1-May-2020
https://doi.org/10.1142/S0129054120500136
Dumitrescu A(2019)A Selectable Sloppy HeapAlgorithms10.3390/a1203005812:3(58)Online publication date: 6-Mar-2019
https://doi.org/10.3390/a12030058
Hofri M(2013)Optimal selection and sorting via dynamic programmingJournal of Experimental Algorithmics (JEA)10.1145/2444016.249337318(2.1-2.14)Online publication date: 15-Aug-2013
https://dl.acm.org/doi/10.1145/2444016.2493373
Show More Cited By

Index Terms

Finding the ith largest of n for small i,n
1. Mathematics of computing
  1. Mathematical analysis
    1. Numerical analysis
      1. Number-theoretic computations
  2. Mathematical software
2. Theory of computation
  1. Design and analysis of algorithms
    1. Data structures design and analysis
      1. Sorting and searching

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Information & Contributors

Information

Published In

cover image ACM SIGACT News

ACM SIGACT News Volume 27, Issue 2

June 1996

51 pages

ISSN:0163-5700

DOI:10.1145/235767

Editor:
Ian Parberry
Univ. of North Texas, Denton

Issue’s Table of Contents

Copyright © 1996 Authors.

Publisher

Association for Computing Machinery

New York, NY, United States

Publication History

Published: 01 July 1996

Published in SIGACT Volume 27, Issue 2

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Cited By

Chen KDumitrescu A(2020)Selection Algorithms with Small GroupsInternational Journal of Foundations of Computer Science10.1142/S012905412050013631:03(355-369)Online publication date: 1-May-2020
https://doi.org/10.1142/S0129054120500136
Dumitrescu A(2019)A Selectable Sloppy HeapAlgorithms10.3390/a1203005812:3(58)Online publication date: 6-Mar-2019
https://doi.org/10.3390/a12030058
Hofri M(2013)Optimal selection and sorting via dynamic programmingJournal of Experimental Algorithmics (JEA)10.1145/2444016.249337318(2.1-2.14)Online publication date: 15-Aug-2013
https://dl.acm.org/doi/10.1145/2444016.2493373
Eusterbrock J(2005)Program synthesis from examples by theory formationFoundations of Intelligent Systems10.1007/3-540-63614-5_36(370-380)Online publication date: 25-Jul-2005
https://doi.org/10.1007/3-540-63614-5_36

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