select and partition

(classic problem)

Definition: Given an array A of n elements and a positive integer k ≤ n, find the k^th smallest element of A and partition the array such that A[1], ..., A[k-1] ≤ A[k] ≤ A[k+1], ..., A[n].

See also select k^th element, Select, MODIFIND, Find.

Note: Algorithms to solve this problem are often used in sort algorithms or to find the median of a set. These can be easily changed to find the k^th largest element.

Author: VZ

Implementation

Vladimir Zabrodsky's analysis and comparison (Rexx), (Scheme)

Go to the Dictionary of Algorithms and Data Structures home page.

If you have suggestions, corrections, or comments, please get in touch with Paul E. Black.

Entry modified 31 July 2009.
HTML page formatted Tue Dec 6 16:16:32 2011.

Cite this as:
Vladimir Zabrodsky, "select and partition", in Dictionary of Algorithms and Data Structures [online], Paul E. Black, ed., U.S. National Institute of Standards and Technology. 31 July 2009. (accessed TODAY) Available from: http://www.nist.gov/dads/HTML/selectAndPartition.html