A (likely really simple) random number generator question

[Acolyte]

Preface: Yes, I know. I'm a noob. I'm currently in an Intro to Programming class at university. So, I'm betting everybody here can answer this question, and I'm gonna feel silly for not knowing the obvious answer. But, hey, whatever gets my assignments done.

Anyways. Here's part of an assignment I'm working on:

#include <stdio.h>
#include <time.h>
 
int rand(void);
void srand(unsigned int seed);
int randnum (int);
void main (void)
 
{
        int r, c, m, n, rnum;
        printf("Please enter the size of the array: ");
        scanf("%d %d", &m, &n);
        int array[m][n];
        for (r = 0; r < n; r++)
        {
                for (c = 0; c < m; c ++)
                {
                        array[r][c] = randnum(rnum);
                        printf("%d", array[r][c]);
                }
        printf("\n");
        }
}
 
int randnum (int rnum)
 
{
        srand(time(NULL));
        rnum = rand() % 100;
        return rnum;
}
 

What I want it to do is produce a different random number for each slot in the array, instead it's just populating it with the same random number. I'm guessing I need a way to re-call the randnum function every time, but I'm not sure how to go about doing that.
Any help would be much appreciated!

[RedSon]

This should get you started:

http://www.cplusplus.com/reference/clibrary/cstdlib/

Everytime you enter your loop you do

 array[i] = rand(); 

EDIT

Sorry I misread your code.

The method srand should be called once during the execution of your program. Everytime you initialize the random number generator with Time(NULL) you start the pseudo random number sequence over again. Take the srand method out of your function and call it in the construictor or at the beginning of your main method.

[Acolyte]

Beautiful, thanks!

Knew it was something small like that.

[RedSon]

Also make sure you realize the implications of this line of code

        srand(time(NULL));

You may want to re-think this if your teacher expects different results for each seperate execution of your exe.