An optimal parallel algorithm for the multiselection problem
نویسنده
چکیده
Given a set S of n elements drawn from a linearly ordered set, and a set K = {k1, k2, . . . , kr} of positive integers between 1 and n, the multiselection problem is to select the kith smallest element for all values of i, 1 ≤ i ≤ r. We present a simple optimal algorithm to solve this problem that runs in O(n log r) time on the EREW PRAM with n1− processors, 0 < < 1.
منابع مشابه
Eecient P Arallel Algorithms for Selection and Multiselection on Mesh-connected Computers Short Version
Let S be a set of n unordered elements, and K be an array of r integers, namely ranks, where r n. The problem of multiselection requires to select the kith smallest (largest) element from S for i = 1; . . . ; r. For sequential multiselection, Fredman et al. [4] established a tight lower bound of (n log r) time. This is consistent with the inherent complexity of multiselection that falls in betw...
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عنوان ژورنال:
- Parallel Computing
دوره 27 شماره
صفحات -
تاریخ انتشار 2001