While the OP did say optimize memory, lookup times for a hash are O(1) and for an array O(N).
The choice is really 1 of fast fetch versu slows fetch,slow lookup vs fast lookup,small footprint verus large.

Yves

Update
That should read O(f(N)) where f(n) changes depending on additional factors about the data in the array, such as if its sorted etc.
Sorry.

In reply to Re: Re: Array vs. Hash (newbie perlguts) by demerphq
in thread Array vs. Hash (newbie perlguts) by perchance

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