UINT_FAST64_MAX
#ifndef UINT_FAST64_MAX
nrand = rand_max < UINT_FAST64_MAX ? rand_max + 1 : 0,
rmod = INT_MAX < UINT_FAST64_MAX ? 0 : UINT_FAST64_MAX / nrand + 1,
rmax = rmax < rmax1 ? rmax1 : UINT_FAST64_MAX;
} while (rmax < UINT_FAST64_MAX);