Forum Post: RE: I Need a help according to Random Number

Hi Giung,

Here is the source for both functions.

//*****************************************************************************
//! Set the random number generator seed.
//!
//! \param ulSeed is the new seed value to use for the random number generator.
//!
//! This function is very similar to the C library <tt>srand()</tt> function.
//! It will set the seed value used in the <tt>urand()</tt> function.
//!
//! \return None
//*****************************************************************************
void
usrand(unsigned long ulSeed)
{
    g_ulRandomSeed = ulSeed;
}

//*****************************************************************************
//! Generate a new (pseudo) random number
//!
//! This function is very similar to the C library <tt>rand()</tt> function.
//! It will generate a pseudo-random number sequence based on the seed value.
//!
//! \return A pseudo-random number will be returned.
//*****************************************************************************
int
urand(void)

{

    // Generate a new pseudo-random number with a linear congruence random
    // number generator.  This new random number becomes the seed for the next
    // random number.

g_ulRandomSeed = (g_ulRandomSeed * 1664525) + 1013904223;

    // Return the new random number.

return((int)g_ulRandomSeed);
}

Here would be an example of usage.

int main (int argc, char *argv[]){

unsigned long ulNewSeed = 3458;

unsigned int newRand;

usrand(ulNewSeed);

newRand = urand();

return 0;

}

Hope this answers your question.