Just as an aside, if you had lazy lists (coming in perl6) and the appropriate sort, the following should run in optimal O(X*log(N)) time, straight out of the box. 
@topN = (sort @X)[0..($N-1)];

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-- All code is 100% tested and functional unless otherwise noted.

In reply to Re: Better mousetrap (getting top N values from list X) by sleepingsquirrel
in thread Better mousetrap (getting top N values from list X) by Limbic~Region

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