KEYWIDTH
n = (size_t)((addrlen / KEYWIDTH) + ((addrlen % KEYWIDTH != 0)?1:0));
return (int)(addr[n/KEYWIDTH]>>((KEYWIDTH-1)-(n%KEYWIDTH))) & 1;
addrkey_t c = key1[n/KEYWIDTH] ^ key2[n/KEYWIDTH];
return (int)(c >> ((KEYWIDTH-1)-(n%KEYWIDTH))) & 1;
n = (size_t)((addrlen / KEYWIDTH) + ((addrlen % KEYWIDTH != 0)?1:0));