#!/usr/bin/perl

# run this like:
# foo.pl <number_of_cols>
# foo.pl 5

use strict;

# get user input for the number of columns
my $cols = $ARGV[0] || 2;

my @images = qw(1.gif 2.gif 3.jpg 4.png 5.jpg);

my $pos = 0;
my $row = 0;
my @rowdata;
foreach my $file (sort @images) {
   $rowdata[$row][$pos] = qq|<tr>\n| if $pos == 0;

   $rowdata[$row][$pos] .= qq|  <td><img src="$file">$file</td>|;

   if (($pos > 0 && $pos % ($cols-1) == 0) || $cols == 1) {
      # we just filled the last position. Reset.
      $rowdata[$row][$pos] .= qq|\n</tr>\n|;
      $pos = 0;
      $row++;
   } else {
      $pos++;
   }
}

unless ($pos == 0) {
   $rowdata[$row][$pos++] = qq|  <td>&nbsp;</td>| until $pos == $cols;
   $rowdata[$row][$pos]  .= qq|</tr>\n|;
}

print join("\n",@{$_}) for @rowdata;