Hi,
lets say I have a iterator of the type:
list<string>::c onst_iterator itr;
lets say its at some position in a given list. Now I can goto the next item
by simply doing a itr++. But I want to increment more than just 1. Lets says
I want to increment the itr 3 times, ie being able to do something like
itr+=3. But as the += is not defined for that iterator class, I cant do
that. What should I do?
Regards,
-ab.
2  1176 
On Wed, 13 Dec 2006 22:42:32 +0500, "Abubakar" <em**********@y ahoo.com>
wrote:
>Hi,
lets say I have a iterator of the type:
list<string>:: const_iterator itr;
lets say its at some position in a given list. Now I can goto the next item
by simply doing a itr++. But I want to increment more than just 1. Lets says
I want to increment the itr 3 times, ie being able to do something like
itr+=3. But as the += is not defined for that iterator class, I cant do
that. What should I do?
Look into std::advance. It can handle any iterator type and will repeatedly
increment non-random access iterators as necessary. The operator isn't
provided for non-random access iterators to emphasize that increment values
1 aren't as simple and efficient as pointer arithmetic.
--
Doug Harrison
Visual C++ MVP
Wow, pretty cool. Thanks :)
-ab.
"Doug Harrison [MVP]" <ds*@mvps.orgwr ote in message
news:bs******** *************** *********@4ax.c om...
On Wed, 13 Dec 2006 22:42:32 +0500, "Abubakar" <em**********@y ahoo.com>
wrote:
>>Hi,
lets say I have a iterator of the type:
list<string>: :const_iterator itr;
lets say its at some position in a given list. Now I can goto the next
item
by simply doing a itr++. But I want to increment more than just 1. Lets
says
I want to increment the itr 3 times, ie being able to do something like
itr+=3. But as the += is not defined for that iterator class, I cant do
that. What should I do?
Look into std::advance. It can handle any iterator type and will
repeatedly
increment non-random access iterators as necessary. The operator isn't
provided for non-random access iterators to emphasize that increment
values
>1 aren't as simple and efficient as pointer arithmetic.
--
Doug Harrison
Visual C++ MVP
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