Old question in a new bottle:
What if i delete a 1D array and again use new to allocate a bigger (or
smaller) size?
is this ok? Feel free to shoot me!
int *array;
int size = 100;
//allocate memory for 'size' no of integers.
array = new int[size];
//fill up the 'array'.
for (int i=0; i<100; i++) array[i] = i;
//delete data pointed to by 'array'
delete[] array;
//again allocate but a bigger size!!
//is this ok??
array = new int[200];
//fill up the 'array'.
for (int i=0; i<200; i++) array[i] = i;
//delete data pointed to by newly allocated 'array'
delete[] array;
Compiler specifics: Microsoft visual studio ver 6.0 and higher.
What I know: it can be done using STL, I KNOW. But how right/wrong is
the above approach?
9  1677  di************@gmail.com wrote:
What if i delete a 1D array and again use new to allocate a bigger (or
You never 'allocate again', you just allocate. The fact that you assign the
result of the allocation to the same pointer than a previous allocation is
completely irrelevant.
--
Salu2
On Jan 8, 4:49 am, Julián Albo <JULIANA...@terra.eswrote:
divya_ratho...@gmail.com wrote:
What if i delete a 1D array and again use new to allocate a bigger (orYou never 'allocate again', you just allocate. The fact that you assign the
result of the allocation to the same pointer than a previous allocation is
completely irrelevant.
--
Salu2
pardon me.. but that means..?
Would it work or not?
thanks in advance!
>
--
Salu2pardon me.. but that means..?
Would it work or not?
and moreover, is it an acceptable practice?
thanks again in advance..
cheers!
"di************@gmail.com" <di**********@gmail.comwrote in message
news:11**********************@s80g2000cwa.googlegr oups.com...
--
Salu2pardon me.. but that means..?
Would it work or not?
and moreover, is it an acceptable practice?
thanks again in advance..
cheers!
Yes it would work. Yes, I've seen it done. Where you would do this depends
on your program.
I can see std::vector doing this exact thing (not sure if it does, but I
could see it implemented this way). di************@gmail.com wrote:
>pardon me.. but that means..?
Would it work or not?
and moreover, is it an acceptable practice?
It works and is acceptable.
--
Salu2
"di************@gmail.com" <di**********@gmail.comwrote:
Old question in a new bottle:
What if i delete a 1D array and again use new to allocate a bigger (or
smaller) size?
is this ok?
Yes, it is OK, though I suggest you use std::vector instead.
int *array;
int size = 100;
I believe the above needs to be a const int.
//allocate memory for 'size' no of integers.
array = new int[size];
//fill up the 'array'.
for (int i=0; i<100; i++) array[i] = i;
//delete data pointed to by 'array'
delete[] array;
//again allocate but a bigger size!!
//is this ok??
array = new int[200];
//fill up the 'array'.
for (int i=0; i<200; i++) array[i] = i;
//delete data pointed to by newly allocated 'array'
delete[] array;
On Jan 8, 6:31 am, Julián Albo <JULIANA...@terra.eswrote:
divya_ratho...@gmail.com wrote:
pardon me.. but that means..?
Would it work or not?
and moreover, is it an acceptable practice?
>It works and is acceptable.
--
Salu2
Thanks a lot, Jim and Julián! I will do some tests and revert back
with my observations.
thanks again :)
- divya rathore
(remove all underscores for email ID)
"Daniel T." <da******@earthlink.netwrote in message
news:da****************************@news.west.eart hlink.net...
"di************@gmail.com" <di**********@gmail.comwrote:
>Old question in a new bottle:
What if i delete a 1D array and again use new to allocate a bigger (or
smaller) size?
is this ok?
Yes, it is OK, though I suggest you use std::vector instead.
>int *array;
int size = 100;
I believe the above needs to be a const int.
Why? For the 'array = new int[size];' statement? That's not true, of course
new array expressions can take nonconst integrals, otherwise they would be
pretty useless :)
- Sylvester
"Sylvester Hesp" <s.****@oisyn.nlwrote:
"Daniel T." <da******@earthlink.netwrote:
"di************@gmail.com" <di**********@gmail.comwrote:
Old question in a new bottle:
What if i delete a 1D array and again use new to allocate a bigger (or
smaller) size?
is this ok?
Yes, it is OK, though I suggest you use std::vector instead.
int *array;
int size = 100;
I believe the above needs to be a const int.
Why? For the 'array = new int[size];' statement? That's not true, of course
new array expressions can take nonconst integrals, otherwise they would be
pretty useless :)
True, my mistake. I was thinking about auto arrays. This thread has been closed and replies have been disabled. Please start a new discussion. Similar topics
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