die "No file name" unless @ARGV;

my @packets = ();
my $short = 9999;

while (<>)
{
 push(@packets,$_);
 if (length($_)-1 < $short)
 {
  $short = length($_) -1; # Find shortest packet
 }
}
chop(@packets);


my $maxlen =0;
my $index = 0;
my $curpack;
my %all;
foreach $curpack (@packets)
{
 #Iterate over packets
 $maxlen = length($curpack);
 for (my $fsize = 2; $fsize <= $maxlen; $fsize ++)
 {
  #Check size 2..$maxlen substrings
  for (my $pnum = 0; $pnum < @packets; $pnum ++)
  {
   #Iterate over packets to check against
   for (0..($maxlen-$fsize+1))
   {
    #Don't compare against self or shorter strings
    if (($index != $pnum) && ($fsize <= length($packets[$pnum])))
    {
     my $str = substr($curpack,$_,$fsize);
     my @temparr = ($packets[$pnum] =~ /$str/g);
     my $nmatch = @temparr;
     if (defined($all{$str}))
     {
      $all{$str} += $nmatch;
     }
     else
     {
      #Remember to count self
      $all{$str} = $nmatch + 1;
     }
    undef @temparr;
    }
   }
  }
 }
 $index ++;
 print "Comparing packet ",$index," to all others:\n";
 my $value;
 my @sort = sort {length($b) <=> length($a)} keys %all;
 foreach $value (@sort)
 {
  #Show only results in >1 packet
  if ($all{$value} > 1) 
  {
   print "(",length($value),") $value: $all{$value} times\n";
  }
  delete($all{$value});
 }
 undef @sort;
}

exit;