Improvements on the accelerated integer GCD algorithm
โ Scribed by Mohamed S. Sedjelmaci; Christian Lavault
- Publisher
- Elsevier Science
- Year
- 1997
- Tongue
- English
- Weight
- 493 KB
- Volume
- 61
- Category
- Article
- ISSN
- 0020-0190
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โฆ Synopsis
The present paper analyses and presents several improvements to the algorithm for finding the (a, b)-pairs used in the k-ary reduction of the right-shift k-ary integer GCD algorithm. While the worst-case complexity of the "Accelerated integer GCD algorithm" is 0( (log,( k))'), we show that the worst-case number of iterations of the while loop is exactly t(k) = $ [log,( k)J (where 4 = $ ( 1 + a) ). We suggest improvements on the latter algorithm and present two new faster residual algorithms: the sequential and the parallel one. A lower bound on the probability of avoiding the while loop in our parallel residual algorithm is also given.
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