Indexing array...

[ditiem]

I hope this is the correct group. It came out a doubt about speed
when indexing an array in the following way:

for a given pointer p, p[0] contains an address and p[1] an offset.
I must return the content of the address plus the offset.. Which way
is faster and more portable?

1.- *( ((unsigned int*)*p) + *(p+1) ) ;
2.- ((unsigned int*)*p)[ *(p+1) ] ;
3.- *((unsigned int*)(*p ++ + *p)) ;

thanks!

[santosh]

On Wednesday 18 Jul 2007 6:51 pm, in comp.lang.c, di****@gmail.com <
di****@gmail.comwrote:
Message ID: <11*********************@z24g2000prh.googlegroups. com>

I hope this is the correct group. It came out a doubt about speed
when indexing an array in the following way:

for a given pointer p, p[0] contains an address and p[1] an offset.
I must return the content of the address plus the offset.. Which
way is faster and more portable?

1.- *( ((unsigned int*)*p) + *(p+1) ) ;
2.- ((unsigned int*)*p)[ *(p+1) ] ;
3.- *((unsigned int*)(*p ++ + *p)) ;

In message:
<11**********************@g37g2000prf.googlegroups .com>

You asked exactly the same question and received three responses.
What was wrong with them?

[Coos Haak]

Op Wed, 18 Jul 2007 18:56:41 +0530 schreef santosh:

On Wednesday 18 Jul 2007 6:51 pm, in comp.lang.c, di****@gmail.com <
di****@gmail.comwrote:
Message ID: <11*********************@z24g2000prh.googlegroups. com>

>I hope this is the correct group. It came out a doubt about speed
when indexing an array in the following way:

for a given pointer p, p[0] contains an address and p[1] an offset.
I must return the content of the address plus the offset.. Which
way is faster and more portable?

1.- *( ((unsigned int*)*p) + *(p+1) ) ;
2.- ((unsigned int*)*p)[ *(p+1) ] ;
3.- *((unsigned int*)(*p ++ + *p)) ;

In message:
<11**********************@g37g2000prf.googlegroups .com>

You asked exactly the same question and received three responses.
What was wrong with them?

Perhaps (in fact ;-) he used google groups. They don't show his two, not
yours or the three answers.
--
Coos, using usenet and a newreader

[Default User]

santosh wrote:

On Wednesday 18 Jul 2007 6:51 pm, in comp.lang.c, di****@gmail.com <
di****@gmail.comwrote:
Message ID: <11*********************@z24g2000prh.googlegroups. com>

I hope this is the correct group. It came out a doubt about speed
when indexing an array in the following way:

You asked exactly the same question and received three responses.
What was wrong with them?

Google Groups was broken again yesterday, posts were not getting out to
their users.

Brian

[ditiem]

Perhaps (in fact ;-) he used google groups. They don't show his two, not

yours or the three answers.

yeah... google groups, you are right. If you have any free usenet
server to be used to
read news I would appreciate it a lot.

[santosh]

On Thursday 19 Jul 2007 4:35 pm, di****@gmail.com <
di****@gmail.comwrote in message
<11*********************@n60g2000hse.googlegroups. com>:

>Perhaps (in fact ;-) he used google groups. They don't show his
two, not yours or the three answers.

yeah... google groups, you are right. If you have any free usenet
server to be used to
read news I would appreciate it a lot.

nntp.aioe.org
or
news.aioe.org

also

news.gmane.org