NZDIGITS
flags |= SIGNOK | NDIGITS | NZDIGITS;
if (flags & NZDIGITS)
flags &= ~(SIGNOK|NZDIGITS|NDIGITS);
flags |= SIGNOK | NDIGITS | NZDIGITS;
if (flags & NZDIGITS)
flags &= ~(SIGNOK|NZDIGITS|NDIGITS);