lookup times for a hash are O(1) and for an array O(N).

That's ridiculous. If values are going to be indexed by integers anyway, then if anything, it takes a bit longer to look up a key in a hash than looking it up as an array index. Maybe you're thinking of looking up things in a linked list, ala LISP? Or if you're strictly searching for a value without a key then they're both O(n).

Update: Re: your reply: I figured that was probably what you were talking about, but the original poster seemed to want to index things by integers, and was just wondering whether to use a hash or an regular array, and the issues with doing one or the other. And I've actually seen code like the below in perl programs which made me want to whack the programmer over the head with a hash array :)

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

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