# Assume the following values
$start = 'Dec 1 2003 4 00:00 AM';
$end   = 'Jan 2 2004 5 00:00 AM';

($s_seconds, $s_year) = parse($start);
($e_seconds, $e_year) = parse($end);

if ($s_seconds < $e_seconds) {
    $elapsed = $e_seconds - $s_seconds;

} else {
#
# we must have rolled over to a new year so...
# Grab the remaining seconds in the old year + the seconds in the new year
#
   $elapsed = $e_seconds + ( $s_year - $s_seconds );
}

$days    = (split(/\./, $elapsed / 86400))[0];
$rem     = $elapsed - (86400 * $days);

$hours   = (split(/\./, $rem / 3600))[0];
$rem    -= 3600 * $hours;

$mins    = (split(/\./, $rem / 60))[0];
$seconds = $rem - ($mins * 60);

print "Total time was: $days Days $hours Hrs $mins Mins $seconds Secs\n";

sub parse {
   my($line) = shift;

   my($mth,$day,$year,$hour,$tosplit,$arg) = split(/\s+/, $line);
   my($min, $sec)                          = split(/:/, $tosplit);

# Add 12 if we are in the PM
   if ($arg =~ /PM/) {
      $hour += 12;

# Set hour to 0 if its 12 AM
   } elsif ($hour == 12) {
      $hour = 0;
   }

   my($base, $total) = this_year($mth, $year);

# beginning of the month + base == # of secs since beginning of year
   my($return) = $base + $sec + ($min * 60) + ($hour * 3600) + ($day * 86400);

   return($return, $total);
}


sub this_year {
   my($mth,$year,$thirty,$thirtyo,$tofind,$base,$total, %months);

   ($mth, $year) = @_;

# number of seconds in a month with thirty days and thirty one days
   $thirty  = "2592000";
   $thirtyo = "2678400";

   %months = (
      Jan => [1, $thirtyo ], Feb => [2, '2419200'], Mar => [3, $thirtyo],
      Apr => [4, $thirty  ], May => [5, $thirtyo ], Jun => [6, $thirty],
      Jul => [7, $thirtyo ], Aug => [8, $thirtyo ], Sep => [9, $thirty],
      Oct => [10, $thirtyo], Nov => [11, $thirty ], Dec => [12, $thirtyo]
   );

# Stupid calendar system :P
# Man its way to late to be computing leap years.. stupid stupid system
   if (($year % 4) == 0) {
      $months{Feb}->[1] += '86400';

      if ( ($year % 100) == 0 && ($year % 400) != 0 ) {
         $months{Feb}->[1] -= '86400';
      }
   }

   $tofind = $months{$mth}->[0];

   for ( sort { $months{$a}->[0] <=> $months{$b}->[0] } keys %months ) {
      $base  += $months{$_}->[1] if ($tofind >= $months{$_}->[0]);
      $total += $months{$_}->[1];
   }

   return($base,$total);
}