I understand that scaling issue. In this situation it makes sense to use a Bloom::Filter, basically a compressed bit vector. The algorithm scales well but produces false positives:

http://www.perl.com/pub/a/2004/04/08/bloom_filters.html

You need to loop through the arrays once to create the vector and a second time for the test [N-2..N+2].

In reply to Re^3: Searching parallel arrays. by NiJo
in thread Searching parallel arrays. by BrowserUk

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