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Date: Tue, 19 May 2015 09:15:48 -0600
Subject: Re: Slices time complexity
From: Ian Kelly <ian.g.kelly@gmail.com>
To: Python <python-list@python.org>
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On May 19, 2015 4:16 AM, "Serhiy Storchaka" <storchaka@gmail.com> wrote:
>
> On 19.05.15 12:45, Steven D'Aprano wrote:
>>
>> On Tuesday 19 May 2015 05:23, Mario Figueiredo wrote:
>>>
>>>  From the above link it seems slices work in linear time on all cases.
>>
>>
>> I wouldn't trust that is always the case, e.g. deleting a contiguous
slice
>> from the end of a list could be O(1).
>
>
> It always has linear complexity. You need to decref removed elements.

Only in CPython. The operation might be O(1) in Pypy or Jython.

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<p dir=3D"ltr"><br>
On May 19, 2015 4:16 AM, &quot;Serhiy Storchaka&quot; &lt;<a href=3D"mailto=
:storchaka@gmail.com">storchaka@gmail.com</a>&gt; wrote:<br>
&gt;<br>
&gt; On 19.05.15 12:45, Steven D&#39;Aprano wrote:<br>
&gt;&gt;<br>
&gt;&gt; On Tuesday 19 May 2015 05:23, Mario Figueiredo wrote:<br>
&gt;&gt;&gt;<br>
&gt;&gt;&gt; =C2=A0From the above link it seems slices work in linear time =
on all cases.<br>
&gt;&gt;<br>
&gt;&gt;<br>
&gt;&gt; I wouldn&#39;t trust that is always the case, e.g. deleting a cont=
iguous slice<br>
&gt;&gt; from the end of a list could be O(1).<br>
&gt;<br>
&gt;<br>
&gt; It always has linear complexity. You need to decref removed elements.<=
/p>
<p dir=3D"ltr">Only in CPython. The operation might be O(1) in Pypy or Jyth=
on.</p>

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