my @parts = split /\./ $address;
return (@parts == 4 
   and $parts[0] == 111 
   and $parts[1] == 255 
   and (($parts[2] > 0 and $parts[2] < 56 
    and $parts[3] >= 0 and $parts[3] < 56) 
     or ($parts[2] == 0 and $parts[3] == 0)));