Construction of List Homomorphisms by Tupling and Fusion
نویسندگان
چکیده
List homomorphisms are functions which can be e ciently computed in parallel since they ideally suit the divide-and-conquer paradigm. However, some interesting functions, e.g., the maximum segment sum problem, are not list homomorphisms. In this paper, we propose a systematic way of embedding them into list homomorphisms so that parallel programs are derived. We show, with an example, how a simple, and \obviously" correct, but possibly ine cient solution to the problem can be successfully turned into a semantically equivalent almost homomorphism by means of two transformations: tupling and fusion.
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