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/* fake version of ldiv() */
typedef struct ldiv_t { long quot, rem; } ldiv_t;
ldiv_t ldiv(numer, denom) long numer, denom;
{
	ldiv_t l;
	l.quot = numer / denom;
	l.rem = numer % denom;
	return l;
}
/*-----------------------------------------------------------------*/
/* Efficient and Portable Combined Random Number Generators */
/* Pierre L'Ecuyer */
/* CACM V. 31 N. 6 pp. 742-749, 774, June 1988 */

/* This random number generator has a period of 2e18. */
/* It can be computed with 2 divides and 4 multiplies */
/* where divides return 16 bit quotient and remainder */
/* of a 32 bit number divided by a 16 bit number, and */
/* mulitplies return a 32 bit product of two 16 bit */
/* factors.  The ANSI portable implementation is less than */
/* optimal, since it must be implemented using long arithmetic, */
/* but at least the algorithm can be specified. */

static long s1 = 1;
static long s2 = 1;

void srandl(seed1, seed2) unsigned long seed1, seed2;
{
	s1 = seed1 % 2147483562L + 1;
	s2 = seed2 % 2147483398L + 1;
}

/* uniform distribution in [1 .. 2147483562] */
long randl()
{
	ldiv_t l;
	register long t;

	l = ldiv(s1, 53668L);
	if ((s1 = 40014L * l.rem - 12211 * l.quot) < 0)
		s1 += 2147483563L;
	l = ldiv(s2, 52774L);
	if ((s2 = 40692L * l.rem - 3791 * l.quot) < 0)
		s2 += 2147483399L;
	if ((t = s1 - s2) < 1)
		t += 2147483562L;
	return t-1;
}

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