what is wrong with this

[free2cric]

Hi,
I have declared pointer of pointers **a;
so In a loop I assign a block to a pointer and put a value in it
and then I want to print these values.

My following program doesnt work.

Also How to do same program with int *a[]; (array of pointers).
Any help would really help.

#include <stdio.h>
#include <conio.h>
#include <malloc.h>

void main()
{
int **a;
int v=0;

for (v=0;v<5;v++)
{
*(a+v)=(int *)malloc(sizeof (int));
**(a+v)=v;
}

for (v=0;v<5;v++)
{
printf("%d\n",* *(a+v));
}

exit(0);

}

[pete]

fr*******@yahoo .com wrote:

ur fathers????

abraham and lot.

--
pete

[Flash Gordon]

fr*******@yahoo .com wrote:

Your response belongs *under* the text you are replying to, not above it.

ok guys whaterver u told , it helped me..
Please don't use contractions like "u" you "you" and "ur" for "your". It
makes it *far* harder for others to read what you are saying. In
general, since you want people to help you be nice to them by writing
properly or why should we put in the effort to solve your problems?
but who will free the allocated memory.. ur fathers????

<snip>

If you allocate memory it is up to you to deallocate it. That's why
there is a free function as well as malloc and realloc.
--
Flash Gordon, living in interesting times.
Web site - http://home.flash-gordon.me.uk/
comp.lang.c posting guidelines and intro:
http://clc-wiki.net/wiki/Intro_to_clc

[free2cric]

Flash Gordon

Please don't use contractions like "u" you "you" and "ur" for "your". It
makes it *far* harder for others to read what you are saying.

I dont udenrstand why people can not understand "u" and "ur"
If you can understand C, C++ and complicated coding then its very easy
to understand
i which context "u" and "ur" is used. We are not writing the post to
mr. president to be so correct.

Thanks anyway for your feedback.

bye
cric.

[Vladimir S. Oka]

fr*******@yahoo .com wrote:

Flash Gordon

Please don't use contractions like "u" you "you" and "ur" for "your".
It makes it *far* harder for others to read what you are saying.

I dont udenrstand why people can not understand "u" and "ur"
If you can understand C, C++ and complicated coding then its very easy
to understand
i which context "u" and "ur" is used. We are not writing the post to
mr. president to be so correct.

I'm sure Mr. President wouldn't be happy at your lack of respect.

Silly phonetic abbreviations can be /very/ hard for non-native English
speakers to decode. I'm sure you do have some consideration (if not
respect) for them, don't you? Otherwise: Hau vud ju lajk if aj vrote in
vot aj konsider tu be fonetik ingliš?

Even for native or fluent English speakers they require extra effort to
decode (unless they learned it from age 3, I guess).

Also, /especially/ people who /really/ understand C (C++ is off-topic,
and not necessarily well understood in these parts), live and breathe
syntax correctness, and "u" and "ur" are certainly not correct English
syntax (also, look up "ur" in any German dictionary; C does not support
mixed language programming either).

Hope this clarifies this a little bit for you.

--
BR, Vladimir

From a certain point onward there is no longer any turning back.
That is the point that must be reached.
-- F. Kafka

[websnarf]

fr*******@yahoo .com wrote:

I have declared pointer of pointers **a;
so In a loop I assign a block to a pointer and put a value in it
and then I want to print these values.

My following program doesnt work.

Also How to do same program with int *a[]; (array of pointers).
Any help would really help.

#include <stdio.h>
#include <conio.h>
#include <malloc.h>

void main() {
int **a;
int v=0;

for (v=0;v<5;v++) {
*(a+v)=(int *)malloc(sizeof (int));
**(a+v)=v;
}

for (v=0;v<5;v++) {
printf("%d\n",* *(a+v));
}
exit(0);
}

You are missing the "backbone" allocation. int ** a, is a pointer to
storage which itself points to additional storage for each integer.
You've allocated the storage for each integer, but not to the big
structure to hold these pointers.

If your compiler has good warnings, you could try to crank the warning
levels up and it should tell you that the line with *(a+v) = ... is
writing to the other end of (a+v) without that pointer having
initilizing it. It seems to me that you have to put something like:

a = (int **) malloc (5 * sizeof (int *));

at the beginning.

Remember that each * in your declaration requires you to point that
level at some storage (or to malloc it) directly in your code, while
each [] in your declaration implicitely declares its own storage for
that level (but may require you to calculate the sizeof() in mallocs at
higher levels carefully).

--
Paul Hsieh
http://www.pobox.com/~qed/
http://bstring.sf.net/

[Richard Bos]

fr*******@yahoo .com wrote:

Flash Gordon

Please don't use contractions like "u" you "you" and "ur" for "your". It
makes it *far* harder for others to read what you are saying.

I dont udenrstand why people can not understand "u" and "ur"
If you can understand C, C++ and complicated coding then its very easy
to understand
i which context "u" and "ur" is used. We are not writing the post to
mr. president to be so correct.

Congratulations : you are now officially too stupid to help.

Richard

[Keith Thompson]

rl*@hoekstra-uitgeverij.nl (Richard Bos) writes:

fr*******@yahoo .com wrote:

Flash Gordon

> Please don't use contractions like "u" you "you" and "ur" for "your". It
> makes it *far* harder for others to read what you are saying.

I dont udenrstand why people can not understand "u" and "ur"
If you can understand C, C++ and complicated coding then its very easy
to understand
i which context "u" and "ur" is used. We are not writing the post to
mr. president to be so correct.

Congratulations : you are now officially too stupid to help.

I suggest giving "free2cric" a break, at least tentatively. He admits
not understanding the problem; it's entirely possible that he's
capable of learning. (Even though he's been posting sporadically to
comp.lang.c for over a year, he might have missed the repeated
discussions of why silly abbreviations are a bad idea.)

--
Keith Thompson (The_Other_Keit h) ks***@mib.org <http://www.ghoti.net/~kst>
San Diego Supercomputer Center <*> <http://users.sdsc.edu/~kst>
We must do something. This is something. Therefore, we must do this.

[Richard G. Riley]

On 2006-02-27, Vladimir S. Oka <no****@btopenw orld.com> wrote:

fr*******@yahoo .com wrote:
Silly phonetic abbreviations can be /very/ hard for non-native English
speakers to decode. I'm sure you do have some consideration (if not
respect) for them, don't you? Otherwise: Hau vud ju lajk if aj vrote in
vot aj konsider tu be fonetik ingli??

Even for native or fluent English speakers they require extra effort to
decode (unless they learned it from age 3, I guess).

Also, /especially/ people who /really/ understand C (C++ is
off-topic,
In many circles constant /hiliting/ is seen as obnoxious and
boring. It lights my newsreader like a beacon and for those that don't
support it, it breaks up the English. Please refrain from doing it so
frequently. It is really, really nasty.

and not necessarily well understood in these parts), live and breathe
syntax correctness, and "u" and "ur" are certainly not correct English
syntax (also, look up "ur" in any German dictionary; C does not support
mixed language programming either).

Hope this clarifies this a little bit for you.

[August Karlstrom]

fr*******@yahoo .com wrote:

Hi,
I have declared pointer of pointers **a;
so In a loop I assign a block to a pointer and put a value in it
and then I want to print these values.

My following program doesnt work.

Also How to do same program with int *a[]; (array of pointers).
Any help would really help.

#include <stdio.h>
#include <conio.h>
#include <malloc.h>

void main()
{
int **a;
int v=0;

for (v=0;v<5;v++)
{
*(a+v)=(int *)malloc(sizeof (int));
**(a+v)=v;
}

for (v=0;v<5;v++)
{
printf("%d\n",* *(a+v));
}

exit(0);

}

You probably want something like the following.

#include <stdio.h>
#include <stdlib.h>

#define LEN 5

int main(void)
{
int **a;
int k = 0;

a = malloc(sizeof *a);
a[0] = malloc(LEN * sizeof **a);
for (k = 0; k < LEN; k++) { a[0][k] = k; }
for (k = 0; k < LEN; k++) { printf("%d\n", a[0][k]); }
return 0;
}
August

--
I am the "ILOVEGNU" signature virus. Just copy me to your
signature. This email was infected under the terms of the GNU
General Public License.

[Flash Gordon]

Vladimir S. Oka wrote:

fr*******@yahoo .com wrote:

Flash Gordon

Please don't use contractions like "u" you "you" and "ur" for "your".
It makes it *far* harder for others to read what you are saying.

I dont udenrstand why people can not understand "u" and "ur"
If you can understand C, C++ and complicated coding then its very easy
to understand
i which context "u" and "ur" is used. We are not writing the post to
mr. president to be so correct.

I'm sure Mr. President wouldn't be happy at your lack of respect.

Silly phonetic abbreviations can be /very/ hard for non-native English
speakers to decode. I'm sure you do have some consideration (if not

<snip>

They are also very difficult for certain groups of *native* English
speakers, such as dyslexics (i.e. me). I, for example, will often have
to read a paragraph using those contractions at least twice before I
understand it, the second time much more slowly than normal. If they are
used more that a couple of times I might have to read it several times
because by the time I've decoded "ur" as "your" I've forgotten the rest
of the paragraph.

Given enough *years* of exposure, or months of *real* effort, it is
possible I might become fluent in such contractions. However, unless
someone is going to pay me a *lot* of money to do something that for me
is far harder than programming and which I do not enjoy at all, then I'm
not going to learn these contractions until they have been used in
normal English for several years.
--
Flash Gordon, living in interesting times.
Web site - http://home.flash-gordon.me.uk/
comp.lang.c posting guidelines and intro:
http://clc-wiki.net/wiki/Intro_to_clc