The description of this module says:

Depth and Count are more specific ways to specify tables in relation to one another. Depth represents how deeply a table resides in other tables. The depth of a top-level table in the document is 0. A table within a top-level table has a depth of 1, and so on. Each depth can be thought of as a layer; tables sharing the same depth are on the same layer. Within each of these layers, Count represents the order in which a table was seen at that depth, starting with 0. Providing both a depth and a count will uniquely specify a table within a document.

Programming 101 - look at the problem slowly and describe what needs to be done in simple steps

• Find a table tag preceded by a td tag
• Store that tag and everything up to the end of td tag
• Repeat this globally for the html body

Anon below is correct, rolling your own regex for a pre-tokenised format is the wrong approach.

perlre is not for html

here is my code:

  $ctr=0;
  while(/(<table>[^\000]*?<\/table>)/){
    $text=$1;
    while($text=~/<table>/){
      $tag=$&;
      $ctr=$ctr+1;
      $tag=~s/(<table)/\1$ctr/;
      $text=~s/<table>/$tag/;
    }
    $text=~s/(<table)$ctr>/\1_level$ctr>/g;
    $text=~s/(<\/table)>/\1_level$ctr>/g;
    $ctr=0;
    $text=~s/(<table)[0-9]+>/\1>/g;
    $text=~s/(<\/?)(thead|tbody)([^>]*)?>//g;
    $text=~s/(<\/?)(th)([^>]*)?>/$1td>/g;
    while($text =~ /<a href="([^"]*)">[^\000]*?<\/a>/){
      $href = $1;
      $class = "";
      if($href =~ /^http/i){  $class = "http";}
      if($href =~ /^www/i){   $class = "nohttp";}
      if($href =~ /^mailto/i){$class = "mailto";}
      if($href =~ /^ftp/i){   $class = "ftp";}
      if($class eq ""){
        $text =~ s/<a href="([^"]*)">([^\000]*?)<\/a>/\2/;
      }else{
        $text =~ s/<a href="([^"]*)">([^\000]*?)<\/a>/<remotelink href
+class="$class" href="\1" >\2<\/remotelink>/;
      }
    }
    s/<table>[^\000]*?<\/table>/$text/;
  }

  # Remove table and img tags inside table if an <img /> tag was encou
+ntered
  while (/<table_level(2|3)>[^\000]*?<\/table_level\1>/) {
    $table2=$&;
    if ($table2 =~ /<img /) {
    # Remove all table tags including <img /> tag
    $table2=~s/<\/?(table_level(2|3)|tr|td)(\s+[^>]*)?>|<img\s+[^>]*\/
+>//g;
    s/<table_level(2|3)>[^\000]*?<\/table_level\1>/$table2/;
    }  
    else {
      $table2=~s/(<\/?table_level\d)/$1_temp/g;
      s/<table_level(2|3)>[^\000]*?<\/table_level\1>/$table2/;
    } 
  }
  s/(<\/?table_level\d)_temp/$1/g;

  # Extract table inside table if no <img /> tag was encountered
  # inside the inner table.
  while (/(<table_level1>[^\000]*?<\/table_level1>)/) {
    $table1=$1;
    #$table2="";
    $table="";
    while ($table1=~ /<table_level2>([^\000]*?)<\/table_level2>/) {
      $table2=$1;
      $table=$&;

      # Extract inner table and place it after the second level table 
+ 
      $extracted_table3="";
      while ($table2 =~ s/(<table_level3>[^\000]*?<\/table_level3>)//)
+ {
        $extracted_table3="$extracted_table3\n$1"; 
      }

      $table2=~s/<table_level2>([^\000]*?)<\/table_level2>/$table$extr
+acted_table3/g;
      #$table2=~s/(<table_level2>[^\000]*?<\/table_level2>)/$1$extract
+ed_table3/g;
      s/(<table_level2>[^\000]*?<\/table_level2>)//;
      #$table2=~s/(<\/?table)_level2/$1_2/g;
    }
    $table1=~s/<table_level2>([^\000]*?)<\/table_level2>//;
    $table1=~s/<table_2>([^\000]*?)<\/table_2>//;
    $table1=~s/(<\/?table)_level1/$1/g;
    s/<table_level1>[^\000]*?<\/table_level1>/$table2$table1/;
  }
  s/(<\/?table)_(level\d|\d)/$1/g;
[download]

And here is my sample data

<table>
    <tr>
        <td>
            <table>
                <thead>
                    <tr>
                        <th>Vill</th>
                        <th>Hi</th>
                        <th>Au</th>
                    </tr>
                </thead>
                <tbody>
                    <tr>
                        <td>Aix</td>
                        <td>40</td>
                        <td>27</td>
                    </tr>
                    <tr>
                        <td>Freib</td>
                        <td>30</td>
                        <td></td>
                    </tr>
                    <tr>
                        <td>Gdan</td>
                        <td>20</td>
                        <td>13</td>
                    </tr>
                    <tr>
                        <td>Gd</td>
                        <td>44</td>
                        <td>14</td>
                    </tr>
                    <tr>
                        <td>Gren</td>
                        <td>33</td>
                        <td>22</td>
                    </tr>
                    <tr>
                        <td>Karl</td>
                        <td>26</td>
                        <td></td>
                    </tr>
                    <tr>
                        <td>La</td>
                        <td>31</td>
                        <td>18</td>
                    </tr>
                    <tr>
                        <td></td>
                        <td>30</td>
                        <td>20</td>
                    </tr>
                    <tr>
                        <td>Lyon</td>
                        <td>41</td>
                        <td>19</td>
                    </tr>
                    <tr>
                        <td>Man</td>
                        <td>22</td>
                        <td></td>
                    </tr>
                    <tr>
                        <td>Mar</td>
                        <td>32</td>
                        <td>18</td>
                    </tr>
                    <tr>
                        <td>Mar</td>
                        <td>17</td>
                        <td>13</td>
                    </tr>
                    <tr>
                        <td>Mon</td>
                        <td>36</td>
                        <td>26</td>
                    </tr>
                    <tr>
                        <td>Mul</td>
                        <td>30</td>
                        <td>45</td>
                    </tr>
                    <tr>
                        <td>Mun</td>
                        <td>28</td>
                        <td>23</td>
                    </tr>
                    <tr>
                        <td>Nice</td>
                        <td>41</td>
                        <td>17</td>
                    </tr>
                    <tr>
                        <td>Nims</td>
                        <td>34</td>
                        <td>25</td>
                    </tr>
                    <tr>
                        <td>Nio</td>
                        <td>29</td>
                        <td>21</td>
                    </tr>
                    <tr>
                        <td>Orleans</td>
                        <td>32</td>
                        <td>17</td>
                    </tr>
                    <tr>
                        <td>Pad</td>
                        <td>36</td>
                        <td>20</td>
                    </tr>
                    <tr>
                        <td>Paris</td>
                        <td>24</td>
                        <td>29</td>
                    </tr>
                    <tr>
                        <td>Perk</td>
                        <td>38</td>
                        <td>29</td>
                    </tr>
                    <tr>
                        <td>Poit</td>
                        <td>27</td>
                        <td>24</td>
                    </tr>
                    <tr>
                        <td>Prag</td>
                        <td>26</td>
                        <td>16</td>
                    </tr>
                    <tr>
                        <td></td>
                        <td>23</td>
                        <td>14</td>
                    </tr>
                    <tr>
                        <td>Ren</td>
                        <td>30</td>
                        <td>18</td>
                    </tr>
                    <tr>
                        <td>Rot</td>
                        <td>36</td>
                        <td>27</td>
                    </tr>
                    <tr>
                        <td>Rou</td>
                        <td>45</td>
                        <td>22</td>
                    </tr>
                    <tr>
                        <td>Saint</td>
                        <td>33</td>
                        <td>20</td>
                    </tr>
                    <tr>
                        <td>Salon</td>
                        <td>33</td>
                        <td>18</td>
                    </tr>
                    <tr>
                        <td>Sev</td>
                        <td>63</td>
                        <td>29</td>
                    </tr>
                    <tr>
                        <td>Sop</td>
                        <td>19</td>
                        <td>8</td>
                    </tr>
                    <tr>
                        <td>Stra</td>
                        <td>28</td>
                        <td>26</td>
                    </tr>
                    <tr>
                        <td>Stut</td>
                        <td>26</td>
                        <td></td>
                    </tr>
                    <tr>
                        <td>logne</td>
                        <td>22</td>
                        <td>11</td>
                    </tr>
                    <tr>
                        <td>lon</td>
                        <td>31</td>
                        <td>22</td>
                    </tr>
                    <tr>
                        <td>use</td>
                        <td>28</td>
                        <td>17</td>
                    </tr>
                    <tr>
                        <td>Ts</td>
                        <td>29</td>
                        <td>22</td>
                    </tr>
                    <tr>
                        <td>Val</td>
                        <td>36</td>
                        <td>23</td>
                    </tr>
                    <tr>
                        <td>Zur</td>
                        <td>29</td>
                        <td>22</td>
                    </tr>
                </tbody>
            </table>
        </td>
        <td>
            <table>
                <tr>
                    <td><span><strong>Legend</strong></span></td>
                </tr>
                <tr>
                    <td>
                        <table>
                            <thead>
                                <tr>
                                    <th>head1</th>
                                    <th>head2</th>
                                </tr>
                            </thead>
                            <tbody>
                                <tr>
                                        <td>bon</td>
                                        <td></td>
                                        <td>0 / 25</td>
                                </tr>
                                <tr>
                                        <td>Ton</td>
                                        <td></td>
                                        <td>25 / 50</td>
                                </tr>
                                <tr>
                                        <td>Don</td>
                                        <td></td>
                                        <td>50 / 75</td>
                                </tr>
                                <tr>
                                        <td>Con</td>
                                        <td></td>
                                        <td>75 / 100</td>
                                </tr>
                                <tr>
                                        <td>Trs</td>
                                        <td></td>
                                        <td> 100</td>
                                </tr>
                            </tbody>
                        </table>
                    </td>
                </tr>
            </table>
        </td>
    </tr>
    <tr>
        <td colspan="2"></td>
    </tr>
    <tr>
        <td colspan="2">This is a sample content</td>
    </tr>
    <tr>
        <td colspan="2"></td>
    </tr>
    <tr>
        <td colspan="2">Site : <a href="http://www.yahoo.com" target="
+_blank">www.yahoo.com</a></td>
    </tr>
</table>
[download]

The output should be like, if a table is consists of 3 levels. the level 2 should be at the top of level 1 then level 3 should be at the bottom of level 2.

The output will be:

level2

level3

level1

If there will be a table greater than the 3rd level or the deepest level, it will be outputted at the bottom of the 3rd level.

Example

level2

level3

level4

level5

level6

level7

level8

level1

Hope I explained it well.

Seriously, this is better achieved using one of the HTML::Parser modules. For example take a look at HTML::TokeParser

use strict;
use warnings;
use HTML::TokeParser;
my $p = HTML::TokeParser->new("file.html") # your source file
     ||die "Cant open: $!";
my $depth=0;
while (my $token = $p->get_token) { 
   if (lc(${$token}[1]) eq "table"){
      $depth++ if (${$token}[0] eq "S");
      $depth-- if (${$token}[0] eq "E");
   print "$depth\n";
   }
}
[download]

Try out the code above and see where it takes you
print "Good ",qw(night morning afternoon evening)[(localtime)[2]/6]," fellow monks."