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#include <u.h>#include <libc.h>#include <libsec.h> #define Maxrand	((1UL<<31)-1) ulongnfastrand(ulong n){	ulong m, r;		/*	 * set m to the maximum multiple of n <= 2^31-1	 * so we want a random number < m.	 */	if(n > Maxrand)		sysfatal("nfastrand: n too large"); 	m = Maxrand - Maxrand % n;	while((r = fastrand()) >= m)		;	return r%n;}