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The Countdown Problem

Hutton, Graham


Graham Hutton


We systematically develop a functional program that solves the countdown problem, a numbers game in which the aim is to construct arithmetic expressions satisfying certain constraints. Starting from a formal specification of the problem, we present a simple but inefficient program that solves the problem, and prove that this program is correct. We then use program fusion to calculate an equivalent but more efficient program, which is then further improved by exploiting arithmetic properties.

Journal Article Type Article
Publication Date Nov 1, 2002
Journal Journal of Functional Programming
Print ISSN 0956-7968
Publisher Cambridge University Press (CUP)
Peer Reviewed Peer Reviewed
Volume 12
Issue 6
Institution Citation Hutton, G. (2002). The Countdown Problem. Journal of Functional Programming, 12(6),
Copyright Statement Copyright information regarding this work can be found at the following address: http://eprints.nottingh.../end_user_agreement.pdf


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