Net::Netmask and cidrs2inverse function

[fedexarg]

I have a file which has a list of IP subnet blocks .

Like this

200.61.191.0/30
200.61.191.4/30
200.61.191.12/30

I would like to find the missing subnets that would fill the gaps in
the list. for the complete /24 net.

I ve tried to use the cidrs2inverse function with no luck.

Can someone give an example ? using this or any other module.

Thanks in advance.