PHP array(3,5,6,7,8,11) how do we know the missing values are 1,2,4,9,10
<p>I got a an array like this $ids = array(3,7,6,5,1,8,11) . How do we know the missing values are 2,4,9,10 ?</p>

<p>My expecting $ids values 1,2,3,4,5,6,7,8,9,10,11 and order doesn't matter, it could be 3,5,6,1,2,4,8,9,10,11.</p>

<p>I don't need to fill my array with the missing values I just want to know who's missing</p>
