[m-users.] lists and sets, unordered or ordered.

Zoltan Somogyi zoltan.somogyi at runbox.com
Wed Oct 4 08:10:36 AEDT 2023


On 2023-10-04 07:55 +11:00 AEDT, "Sean Charles (emacstheviking)" <objitsu at gmail.com> wrote:
> Indeed. nothing in my drafts folder and I swear it was complete before I hit send... well,
> basically,
> is there a reason you can't get an unsorted de-duped list from a set?

Yes, there is. The reason is that any algorithm to remove duplicates
from an unsorted list will either

- sort the list (which is O(n log n), or
- have worse efficiency than an algorithm that sorts the list.

Zoltan.


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