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/********************************************************************
The McGill Super-Duper Random Number Generator
G. Marsaglia, K. Ananthanarayana, N. Paul
Incorporating the Ziggurat method of sampling from decreasing
or symmetric unimodal density functions.
G. Marsaglia, W.W. Tsang
Rewritten into C by E. Schneider
*********************************************************************/
static unsigned long mcgn, srgn;
#define MULT 69069L
void rstart (long i1, long i2)
{
mcgn = (unsigned long)((i1 == 0L) ? 0L : i1 | 1L);
srgn = (unsigned long)((i2 == 0L) ? 0L : (i2 & 0x7FFL) | 1L);
}
long uni(void)
{
unsigned long r0, r1;
r0 = (srgn >> 15);
r1 = srgn ^ r0;
r0 = (r1 << 17);
srgn = r0 ^ r1;
mcgn = MULT * mcgn;
r1 = mcgn ^ srgn;
return (r1 >> 1);
}
long vni(void)
{
unsigned long r0, r1;
r0 = (srgn >> 15);
r1 = srgn ^ r0;
r0 = (r1 << 17);
srgn = r0 ^ r1;
mcgn = MULT * mcgn;
r1 = mcgn ^ srgn;
return r1;
}
/*
"Anyone who consider arithmetic means of producing random number is,
of course, in a state of sin" - John Von Neumann
*/
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