title: Regular expression for barcodes (12 or 14 digits)
body: <p>I'm looking for regular expression which will match barcode.  The barcodes can be 12 or 14 digits long (never 13) and the first digit has to be <code>8</code>.  Examples:  </p>
  
  <pre><code>800909887898  
  80903243234323
  </code></pre>
  
  <p>I've got something like this: <code>^[8]{1}[0-9]{11}$</code> but I don't know hot to recognize last 2 digits. It's can be 2 digits character or null (the expression <code>[0-9]{0-2}</code> will not work fine because quantifier don't work like OR).</p>