An n-element knapsack problem has 2" possible solutions to search over, so a task which can be accomplished in 2" trials if an exhaustive search is used. Due to the exponential time in solving the knapsack problem, the problem is considered to be very hard. In the past decade, much effort has been d
Comments on parallel algorithms for the knapsack problem
β Scribed by Carlos Alberto Alonso Sanches; Nei Yoshihiro Soma; Horacio Hideki Yanasse
- Publisher
- Elsevier Science
- Year
- 2002
- Tongue
- English
- Weight
- 65 KB
- Volume
- 28
- Category
- Article
- ISSN
- 0167-8191
No coin nor oath required. For personal study only.
β¦ Synopsis
Chang et al. [Parallel Comput. (1994) 233] introduced a parallel algorithm based on a shared memory SIMD architecture for the generation phase of the classic Horowitz and Sahni [J. ACM 21(2) (1974) 277] two-list serial algorithm for the knapsack problem. They claimed that their parallel generation phase could be accomplished in time Oððn=8à 2 à and in space Oð2 n=4 à with Oð2 n=8 à processors.
We prove that their results are not correct, i.e., that the suggested scheme time and space complexity should be bounded, instead, by OΓ°n2 n=2 Γ and OΓ°2 n=2 Γ, respectively. These results also invalidate the performance analysis of the more recent Lou and Chang [Parallel Comput. (1997) 1985] algorithm.
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