Greetings monks,

As usual, I have a problem that has me a little stumped. I have been using the same code for years to calculate IP addresses. However, now I need to make that manipulation dependent on whether the last octet in a given IP address is odd or even. Basically, if the IP address is 10.1.1.6 for example, I need a new variable to be 10.1.1.5. If the IP address is 10.1.1.5, I need the new variable to be 10.1.1.6. Below is what I have thus far 
#!/usr/bin/perl

print "Enter the IP address\n";
$tunip = <STDIN>;
chomp ($tunip);

my $period=".";
my @ip_fields = split(/\./, $tunip);
my ($bgp_ip,$test_ip);

if ($ip_fields[3] % 2) {
    $test_ip=$ip_fields[3]-1;
} else {
    $test_ip=$ip_fields[3]+1;
}
$bgp_ip = $ip_fields[0].$period.$ip_fields[1].$period.$ip_fields[2].$p
+eriod.$test_ip;

[download]
For some reason, this just leaves '$bgp_ip' blank. Any wisdom at all would be greatly appreciated.

In reply to Need to calculate IP address by ddrew78

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