Use Net::CIDR's cidr2range, sort the ranges, combine the ones that are overlapping or adjacent, then use range2cidr to go back.

-- Randal L. Schwartz, Perl hacker

update Shoot, I totally missed cidradd in the same module, which does precisely that! 
$ perl
use Net::CIDR qw(cidradd);
print join (", ", cidradd(qw{
209.152.214.112/30
209.152.214.116/31
209.152.214.118/31
})), "\n"
^D
209.152.214.112/29
$ perl
use Net::CIDR qw(cidradd);
print join (", ", cidradd(qw{
209.152.214.112/31
209.152.214.116/31
209.152.214.118/31
})), "\n"
^D
209.152.214.112/31, 209.152.214.116/30

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In reply to Re: Challenge Problem: Merging Network Addresses by merlyn
in thread Challenge Problem: Merging Network Addresses by Dominus

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