Andrew Cooper於 2012年8月10日星期五UTC+8上午6時03分26秒寫道：
> On 09/08/2012 22:34, Roman Vashkevich wrote:
>
> > Actually, they are different.
>
> > Put a dict.{iter}items() in an O(k^N) algorithm and make it a hundred
> > thousand entries, and you will feel the difference.
>
> > Dict uses hashing to get a value from the dict and this is why it's O(1).
>
> >
>
>
>
> Sligtly off topic, but looking up a value in a dictionary is actually
>
> O(n) for all other entries in the dict which suffer a hash collision
>
> with the searched entry.
>
>
>
> True, a sensible choice of hash function will reduce n to 1 in common
>
> cases, but it becomes an important consideration for larger datasets.
>
>
>
> ~Andrew
This is the classical problem of storing the hash collision items one by one.
Those items should be stored by some order.
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