Using merlyn's code (see this node):

use strict;

my %hash;
while (<DATA>) {
    # split based on spaces
    my ($hex, $foo, $int) = split /\s+/;
    $hash{$hex}{$int}++;
}

for (keys %hash) {
    print "$_ = ", join(", ", sort keys %{$hash{$_}}), "\n";
}


__DATA__
0x130005d   1.253.54.1      11          
0x130009c   1.253.54.2      12    
0x130005d   1.253.54.1      14     
0x130005d   1.253.54.1      11    
0x130005d   1.253.54.1      10    
0x130009c   1.253.54.2        12    
0x130009c   1.253.54.2        14
[download]

Gives

0x130005d = 10, 11, 14
0x130009c = 12, 14
[download]

--
"I don't intend for this to take on a political tone. I'm just here for the drugs." --Nancy Reagan