Re: [Boost-users] multi_index:iterator_to complexity

Subject: Re: [Boost-users] multi_index:iterator_to complexity
From: Joaquin M Lopez Munoz (joaquin_at_[hidden])
Date: 2015-03-09 03:02:19

Matwey V. Kornilov <matwey.kornilov <at> gmail.com> writes:

> 
> 
> Hi,
> 
> The following two calls have constant complexity (according to docs) for
> all indices:
> 
>     iterator       iterator_to(const value_type& x);
>     const_iterator iterator_to(const value_type& x) const;

Correct, these are constant complexity.

> As far as I understand, the single way to reach the constant complexity
> in searching by pointer is to store the objects in continuous memory area.
> 
> Is it correct?

No, it's not correct. In fact, elements in a multi_index_container are
*not* stored contiguously.

iterator_to does not do any kind of search based on x, but takes a reference
to an element of the container and returns an iterator to it (roughly
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