title: how to shrink consecutive B ip classes in bigger one
body: <p>After reading <a href="https://stackoverflow.com/q/11164672/850781">List of IP Space used by Facebook</a>:</p>
  
  <p>"Real" list is the last answer, but I wonder how Igy (with the answer marked as solution) managed to shrink the list a lot by adding consecutive classes into a bigger one (by decreasing accordingly from network mask for each new consecutive network), is there a tool, or only manually ?</p>
  
  <p>This is a HUGE improvement for firewall, where number of rules counts (the shorter the better).</p>