Re: about new and delete

From:

"Alf P. Steinbach" <alfps@start.no>

Newsgroups:

comp.lang.c++

Date:

Sat, 26 Sep 2009 01:53:44 +0200

Message-ID:

<h9jl2a$511$1@news.eternal-september.org>

* Sam:

Juha Nieminen writes:

Sam wrote:

I'll repeat part of what Richard said for emphasis: "as opposed to any
of the other standard containers"

Repeating the same question will only yield the same answer: "the
ability to collect a list of numbers, of variable size, then iterate
over them for the purpose of printing them back". If you do not
understand what that means, look it up.

And exactly how is that different from any other STL container? Why is
std::list the best solution in this case?

Because, in the OP's poster case, his basic demo program did not require
random access, and std::list won't require obtaining the size of the
list in advance, in order to get the best performance.

Hi.

For the OP's purpose, std::vector does not require obtaining the size of the
list in advance (see the push_back() member routine), and has generally better
performance: push_back is of amortized O(1) complexity. ;-)

I guess that's why people are sort of "upset" about your suggestion of std::list.

Not that it's terribly wrong or that std::vector is so much better or that it
matters at all in this case, and if one starts being pedantic about things then
a case can be made for std::deque as the probably best all-round potato.

But std::list is not generally a good *default* choice: it's a very special
purpose structure.

Cheers & hth.,

- Alf