12 lines
624 B
Text
12 lines
624 B
Text
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This module provides both a C and pure ruby simple subset sum problem
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solver. The subset sum problem is, given a set of numbers, can the sum
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of any subset of those numbers equal a given number. This problem is
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NP-complete.
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Both the C and pure ruby versions implement a fairly simple
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meet-in-the-middle algorithm. The C version uses an AVL tree to store
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the data, while the pure ruby version uses a ruby hash. For the C
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version to be used, the sum of the positive numbers and the sum of the
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negative numbers in the set, as well as the wanted number, must all be
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Fixnums. Additionally, max_seconds should be nil or a Fixnum.
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