Why am I not getting the results I expect...

[Sudhakar Chandra <thaths@xxxxxxxxxxxx>]

Hi,

I have a piece of code where I generate a random number between 1 and n.  I
also want to make sure that each random number is generated only once.

Here is a snippet of code:

int num_of_arts;
int display_article_number;
int * article_displayed;	/* Flags stored here */


num_of_arts = 24;

/* Make enough space to store the flags */
article_displayed = (int *) calloc(num_of_arts, sizeof(int));



display_article_number = 1 + (int) (((float) num_of_arts) * random() /
(RAND_MAX+1.0));

while (*(article_displayed+display_article_number-1) == 1) {
    display_article_number = 1 + (int) (((float) num_of_arts) * random() /
(RAND_MAX+1.0));
}



I expect this piece of code to generate a random number between 1 and 24. 
But it also generates number > 24.  What am I doing wrong?  I got the algo
to generate a random number between 1 and n from the manpage for rand()
(not random()).

Thaths
-- 
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Sudhakar C13n    http://www.aunet.org/thaths/    Lead Indentured Slave