Got it. Thanks On Fri, Dec 20, 2019, 2:34 AM Inada Naoki <songofaca...@gmail.com> wrote:
> On Fri, Dec 20, 2019 at 4:15 PM Wes Turner <wes.tur...@gmail.com> wrote: > > > > How slow and space-inefficient would it be to just implement the set > methods on top of dict? > > Speed: Dict doesn't cache the position of the first item. Calling > next(iter(D)) repeatedly is O(N) in worst case. > Space: It waste 8bytes per member. > > > > > Do dicts lose insertion order when a key is deleted? AFAIU, OrderedDict > do not lose insertion order on delete. > > Dict keeps insertion order after deletion too. > > >Would this limit the utility of an ordered set as a queue? What set > methods does a queue need to have? > > I want O(1) D.popleft(). (The name is borrowed from deque. popfirst() > would be better maybe). > > -- > Inada Naoki <songofaca...@gmail.com> >
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