my $subnet = "40";

for(1..239){
    chomp;
    my $ip = "10.1.$subnet.$_";

    .
    .

}

##</code><code>##

use Net::Netmask;

sub ips {
    my $net = Net::Netmask->new(@_);
    wantarray ? $net->enumerate : \@{$net->enumerate};
}