Question about seeds and random number g

Question about seeds and random number generators.

Okay, my prof gave us an assignment and I wanted to test if my program was working correctly but I'm not sure how to test it so
my question is:

If my prof and I are using both the same compiler (DEV-C++)

and we use the same SEED for Random number generator.

And we may or may not have the same method of generating numbers ...

Are we supposed to supposed to have the same sequence?
For example my code for my random number generator, generates a number 1-4.
int randNum = (rand() % 4)+1)

When I ask it to output 10 random numbers using 789 as my seed (same as prof)
I get

 1,2,1,3,2,1,1,1,1

I don't know what my prof's output is, I just know it isn't the same as mine.

so, if it's from the same compiler are we supposed to have the same exact number(s) generated? Or is it that if you make a difference num generator that you'll get a different output?

Thank you ^-^!

Last edited on

helios (17607)

so, if it's from the same compiler are we supposed to have the same exact number(s) generated?

Not necessarily, but in most cases a compiler by the same developer will use the same algorithm. It's not a safe assumption, though.

Or is it that if you make a difference num generator that you'll get a different output?

Of course.

Ng Han Seng (26)

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

int main ()
{
	int i, x, res;
	scanf("%d", &x);

	srand(x);
	for (i=0; i<10; i++)
	{
		printf("\n > %d", rand()%4+1);
	}
	return 0;
}

well. i tried it on my desktop and laptop, both running C++ express 2010. with this code and 789 as the seed, the results from both are exactly the same :O

Tatipu (83)

Okay thank you (:

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Question about seeds and random number generators.

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