Find the number unsorted
<h2>Find the unsorted/misplaced number</h2>

<p>There is a sorted array <em>(say: <code>[1, 2, 3, 4, 5, 6, 7]</code>)</em>.</p>

<p>Now, some number <em>(say: <code>-2</code>)</em> is inserted "by mistake" <em>(say: <code>[1, 2, 3, 4, -2, 5, 6, 7]</code>)</em>.</p>

<p>How would one got about finding such misplaced number?</p>