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Re: Initializing iterators to one past end() in for loops

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On 04/14/11 10:07 AM, Nikos Chantziaras wrote:
> On 04/14/2011 12:38 AM, Nikos Chantziaras wrote:
>> Is there some simple way to convert this:
>>
>> std::vector<int> vec;
>> // ...
>> for (size_t i = 1; i < vec.size(); ++i)
>> // do something with vec[i]
>>
>> to a for-loop that uses iterators? I've tried:
>>
>> typedef std::vector<int>::iterator it_t;
>> for (it_t i = vec.begin() + 1; i != vec.end(); ++i)
>> // do something with *i
>>
>> but I'm not surprised that it doesn't work.
>
> Thanks for all the responses. But I've made a mistake in my provided
> example :-P In the second loop, I'm using an std::list, not a vector:
>
> std::list<int> lst;
> typedef std::list<int>::iterator it_t;
> for (it_t i = lst.begin() + 1; i != lst.end(); ++i)
> // do something with *i
>
> (Converting some vectors to lists was the reason I came across this in
> the first place.)
>
> I know it's not difficult to simply do something like:
>
> it_t i = lst.begin();
> ++i;
> for ( ; i != lst.end(); ++i)

That would be the usual way.

> but I was wondering whether there's some neat way to do that inside the
> for header, so that 'i' will not stay in scope after the loop.

Put the operation in its own scope (a function maybe)?

-- 
Ian Collins

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Initializing iterators to one past end() in for loops Nikos Chantziaras <realnc@arcor.de> - 2011-04-14 00:38 +0300
  Re: Initializing iterators to one past end() in for loops Leigh Johnston <leigh@i42.co.uk> - 2011-04-13 22:46 +0100
  Re: Initializing iterators to one past end() in for loops Kai-Uwe Bux <jkherciueh@gmx.net> - 2011-04-13 23:48 +0200
    Re: Initializing iterators to one past end() in for loops Leigh Johnston <leigh@i42.co.uk> - 2011-04-13 22:50 +0100
      Re: Initializing iterators to one past end() in for loops Kai-Uwe Bux <jkherciueh@gmx.net> - 2011-04-14 00:23 +0200
        Re: Initializing iterators to one past end() in for loops Kai-Uwe Bux <jkherciueh@gmx.net> - 2011-04-14 00:32 +0200
          Re: Initializing iterators to one past end() in for loops Noah Roberts <dont@email.me> - 2011-04-13 17:16 -0700
            Re: Initializing iterators to one past end() in for loops Kai-Uwe Bux <jkherciueh@gmx.net> - 2011-04-14 05:57 +0200
              Re: Initializing iterators to one past end() in for loops Leigh Johnston <leigh@i42.co.uk> - 2011-04-14 14:29 +0100
                Re: Initializing iterators to one past end() in for loops Kai-Uwe Bux <jkherciueh@gmx.net> - 2011-04-14 17:57 +0200
                Re: Initializing iterators to one past end() in for loops Leigh Johnston <leigh@i42.co.uk> - 2011-04-14 17:56 +0100
                Re: Initializing iterators to one past end() in for loops Kai-Uwe Bux <jkherciueh@gmx.net> - 2011-04-14 19:33 +0200
              Re: Initializing iterators to one past end() in for loops Noah Roberts <dont@email.me> - 2011-04-14 09:54 -0700
                Re: Initializing iterators to one past end() in for loops Kai-Uwe Bux <jkherciueh@gmx.net> - 2011-04-14 20:08 +0200
  Re: Initializing iterators to one past end() in for loops gwowen <gwowen@gmail.com> - 2011-04-13 14:49 -0700
  Re: Initializing iterators to one past end() in for loops Sam <sam@email-scan.com> - 2011-04-13 16:58 -0500
  Re: Initializing iterators to one past end() in for loops Nikos Chantziaras <realnc@arcor.de> - 2011-04-14 01:07 +0300
    Re: Initializing iterators to one past end() in for loops Ian Collins <ian-news@hotmail.com> - 2011-04-14 10:12 +1200
    Re: Initializing iterators to one past end() in for loops gwowen <gwowen@gmail.com> - 2011-04-13 15:24 -0700
    Re: Initializing iterators to one past end() in for loops Paavo Helde <myfirstname@osa.pri.ee> - 2011-04-13 23:05 -0500
      Re: Initializing iterators to one past end() in for loops Ian Collins <ian-news@hotmail.com> - 2011-04-14 16:20 +1200
        Re: Initializing iterators to one past end() in for loops Paavo Helde <myfirstname@osa.pri.ee> - 2011-04-13 23:52 -0500
        Re: Initializing iterators to one past end() in for loops Jeff Flinn <TriumphSprint2000@hotmail.com> - 2011-04-14 07:49 -0400
      Re: Initializing iterators to one past end() in for loops Nikos Chantziaras <realnc@arcor.de> - 2011-04-14 21:45 +0300

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