Sum of a table column - SMARTY - smarty

Question

I have a multidimensional associative array, which I pass to a smarty template. I use below code in my smarty template to generate the shown two tables in my browser.
The smarty code:
<!--language:smarty-->
{foreach from=$allarr key=header item=table}
<h5>{$header}</h5>
<table>
<tr>
<td>{t}Emp #{/t}</td>
<td>{t}Employee Name{/t}</td>
<td>{t}Amount{/t}</td>
</tr>
{foreach from=$table item=sub}
<tr>
<td>{$sub.emp_num}</td>
<td>{$sub.user_name}</td>
<td>{$sub.amount}</td>
</tr>
{/foreach}
<tr>
<td colspan="2">{t}Variation Total{/t}</td>
<td colspan="1">{t}+++{/t}</td>
</tr>
</table>
{/foreach}
The tables:
Table One
________________________________
Emp # |Employee Name |Amount |
________|_______________|_______|
1000001 | Test User | 775.00|
26 | user1 | 555.00|
________|_______________|_______|
Variation Total | +++ |
________________________|_______|
Table Two
______________________________
Emp # |Employee Name| Amount|
________|_____________|_______|
1000001 | Test User | 110.00|
________|_____________|_______|
Variation Total | +++ |
______________________|_______|
What I want, is to replace the "+++" with the actual sum of the values in each Amount column. Nothing seems to work. Can anyone help? Thanks in advance.

Answer 1

Figured out a way. :)
The complete code is below.
{foreach from=$allarr key=header item=table}
<h5>{$header}</h5>
<table>
<tr>
<td>{t}Emp #{/t}</td>
<td>{t}Employee Name{/t}</td>
<td>{t}Amount{/t}</td>
</tr>
{foreach from=$table item=sub}
<tr>
<td>{$sub.emp_num}</td>
<td>{$sub.user_name}</td>
<td>{$sub.amount}</td>
</tr>
{assign var="sum" value="`$sum+$sub.amount`"}
{/foreach}
<tr>
<td colspan="2">{t}Variation Total{/t}</td>
<td colspan="1">{t}{$sum}{/t}</td>
{assign var="sum" value=0}
</tr>
</table>
{/foreach}