title: Regular expression for 6 digit number with optional 2 decimal digits
body: <p>I need a regular expression for 6 digit number with optional 2 decimal digit
  <strong>Allowed values:</strong></p>
  
  <pre><code>    .1  .11  0.11  10. 10.1   10.12  00.00  0.0  00.00
  
     123456 12345 1234 123 12 1 0 0. 123. 123.55 123456.  
  </code></pre>