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From: "Alex Vinokur" <alexvn AT foot DOT com>
Newsgroups: comp.os.msdos.djgpp
Subject: Re: Trouble of using very large arrays
Date: Fri, 23 Apr 2004 20:48:04 +0300
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"CBFalconer" <cbfalconer AT yahoo DOT com> wrote in message news:40894F42 DOT B60859A7 AT yahoo DOT com...
> Alex Vinokur wrote:
> > "Martin Ambuhl" <mambuhl AT earthlink DOT net> wrote in message
> >> Cesar Rabak wrote:
> >>> Brian Inglis escreveu:
> >>
> >>>> this is cleaner and more maintainable:
> >>>>
> >>>> a = malloc(rows * columns * sizeof *a);
> >>>>
> >>> This is not a good advice: you're changing the allocation of an
> >>> object of (rows x columns) ints to another of (rows x columns)
> >>> pointers to int.
> >>
> >> You are, I regret to say, in error.  The type of *a is int, not
> >> pointers-to-int.
> >

------ My mistake ------
> > You are right. So,
> >  a = malloc(rows * columns * sizeof  a);
------------------------
>                                       ^^
> No no, 1000 times no, that should be "*a".
>

Of course,
char* a1 = malloc(rows * columns * sizeof  *a1);  /* malloc(rows * columns * sizeof  (char));  */
int* a2 = malloc(rows * columns * sizeof  *a2);   /* malloc(rows * columns * sizeof  (int));  */
long* a3 = malloc(rows * columns * sizeof  *a3);  /* malloc(rows * columns * sizeof  (long));  */

[snip]


--
   Alex Vinokur
     mailto:alexvn AT connect DOT to
     http://mathforum.org/library/view/10978.html