Smarty - Difficult if else to make select options - foreach

Question

I am having real trouble getting my head around this smarty else if.
For each
{foreach $values as $value}
{if $value = a}
do action
{elseif $value = b}
do action
{elseif $value = c}
do action
{/if}
{/foreach}
I only want to 'do action' once for the entire foreach. For any one iteration of the foreach a differnt condition(a b or c) might be = to $value
The real world example that I am working on is adding 'selected' to a drop down option.
<select>
{foreach $offices as $office}<!-- The if below is done so that the form is sticky, and when editing a post, it shows the post's current setting.-->
<option
{if $smarty.post.OfficeCode == $office.OfficeCode}
selected='selected'
{elseif $bulletin_array[0].OfficeCode == $office.OfficeCode}
selected='selected'
{elseif $office.OfficeCode == $UsersOffice}
selected='selected'
{/if}
title='{$office.Description}' value='{$office.OfficeCode}'>{$office.Title}
</option>
{/foreach}
</select>
the first if will be true if the form has been submited - to make the form sticky
the second part will be true the form is being pre-filled when editing the record - ie prefil the form with the current value
the third part will be true if the user is creating a new record, in which case set it to a default option that the user usually uses.
I need some way of only allowing selected to be added once.
I php I would have a variable outside the foreach which was set to true if selected was added. I would then check that variable before doing the if elseif

Answer 1

{if ($smarty.post.OfficeCode eq $office.OfficeCode)
or ($bulletin_array[0].OfficeCode eq $office.OfficeCode)
or ($office.OfficeCode eq $UsersOffice)}
selected='selected'
{/if}