title: Regex to find lines that match a specific pattern
body: <p>I have a txt file and it has the data has a <code>///////////</code>  to divide the results. I need to find the results that only have 1 line.</p>
  <p>I've tried but I can't seem to figure out how to differentiate the multiple lines between the <code>///////////</code></p>
  <p>For example, I just need to find the a and the d.</p>
  <pre><code>/////////// 
  a
  ///////////
  b
  c
  //////////
  d
  /////////
  </code></pre>