title: Batch script to merge lines from two files into a third file
body: <p>Contents of file <code>A1</code>:</p>
  
  <pre><code>AA
  VV
  BB
  </code></pre>
  
  <p>Contents of file <code>A2</code>:</p>
  
  <pre><code>DD
  EE
  FF
  </code></pre>
  
  <p>I want to merge the contents of <code>A1</code> and <code>A2</code> as below into <code>A3</code>, so that the expected data in <code>A3</code> is:</p>
  
  <pre><code>AADD
  VVEE
  BBFF
  </code></pre>
  
  <p>Alternatively, the expected output in <code>A3</code> may be:</p>
  
  <pre><code>AA is from DD
  VV is from EE
  BB is from FF
  </code></pre>
  
  <p>Thanks for the help. I did try and search before I posted and could not find someone that has already posted something similar...</p>