use NetAddr::IP;

#$hosts= '172.21.3.128-172.21.3.140;10.1.1.1;192.168.0.1/8';
#$hosts= '172.21.3.128-172.21.3.140;10.1.1.1;10.0.0.0/30';
push @hosts, split ';', $hosts;

for my $cidr( @hosts ) {
    print "$cidr\n";
    my $n = NetAddr::IP->new( $cidr );
    for my $ip( @{$n->hostenumref} ) {
        print "\t", $ip->addr, "\n";
    }
}