title: compare strings and get end difference
body: <p>I have two strings.<br />
  String A: &quot;The quick brown fox&quot;<br />
  String B: &quot;The quick brown fox jumps over the lazy dog.&quot;</p>
  <p>String B will always contain string A verbatim. There will never be a &quot;quick black fox&quot; or a &quot;quick and speedy brown fox&quot;.</p>
  <p>How do I get a &quot;String C&quot; of the difference &quot;jumps over the lazy dog.&quot;?</p>