title: Help in writing REGEX
body: <p>I have to take user input from a HTML form in this format (field1)(space)(field2) where both field1 and field2 are Strings but the restrictions are:</p>
  
  <ul>
  <li>field1 &amp; field2 can't be integers</li>
  <li>they must be alphanumeric</li>
  <li>they should not start with the same character</li>
  </ul>
  
  <p>Note that this pattern can repeat itself, eg:<br>
  <code>abc def ghi jkl</code></p>