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From: Tim Rentsch <tr.17687@z991.linuxsc.com>
Newsgroups: comp.lang.c++
Subject: Re: This code is effective for modest-sized numbers, but can you tell what it does?
Date: Mon, 25 Apr 2022 05:27:27 -0700
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Juha Nieminen <nospam@thanks.invalid> writes:

> Graeme C. <graec58@gmail.com> wrote:

[...]

>>    for (int i=0; i<vf[gen-1].size(); i++) { // from previous gen
>
> std::vector::size() returns a value of type std::size_t.  You
> shouldn't be using an int with it.

I don't want to start a holy war, but in this particular case
there is no problem comparing a signed type to a size_t (which is
an unsigned type).  More generally, whenever a value of a signed
type has a non-negative value, as is obviously true in this
construct, then there is never a problem comparing a value of a
signed type to a value of an unsigned type.

Some people prefer using an unsigned type for indexing variables
like 'i' above, and that a reasonable style choice here IMO.  But
there is nothing logically wrong with giving 'i' a signed type
here instead.