I quite intentionally did not say one would be always be "faster". I said reverse sort is less efficient. sort and reverse sort are both O(n log n), but the one with reverse has a larger constant factor and is less efficient.

By the way, if you want to know the fastest way to sort the list (1..100_000) in descending order, it's: reverse (1 .. 100_000); ;)

Update: Doh. As Tilly explains below, I totally messed up the Big O analysis. Anyway, there is an added inefficiency with reverse sort, that's my point. :)

In reply to Re: Re: Re: Re: reversing a sort... by chipmunk
in thread reversing a sort... by suaveant

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