How to find the sum of values ​​in a variable?

Question

PHP

Hello. There is such a code. smarty template engine. How to get the amount of {$item.cartitem.amount} ?

{foreach $order_data.items as $n=>$item}
      <tr class="tr">
        <td class="td">{$item.cartitem.amount}</td>
      </tr>
    {/foreach}

Answer 1

{count($item.cartitem.amount)}