shithub: plan9front

ref: 4b8f7a2110d80fdad0f09f376dbfd2204e2e8f8e
dir: /sys/src/ape/lib/v/nrand.c/

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#include <stdlib.h>

#define	MASK	0x7FFFFFFFL
#define	FRACT	(1.0 / (MASK + 1.0))

extern long lrand(void);

double
frand(void)
{

	return lrand() * FRACT;
}

nrand(int n)
{
	long slop, v;

	slop = MASK % n;
	do
		v = lrand();
	while(v <= slop);
	return v % n;
}