title: string padded with optional blank with max length
body: <p>I have a problem building a regex. this is a sample of the text:</p>
  
  <pre><code>text 123 12345 abc 12    def 67 i 89 o 0    t 2
  </code></pre>
  
  <p>The numbers are sometimes padded with blanks to the max length (3).
  e.g.:</p>
  
  <ul>
  <li>"1" can be "1" or "1  "</li>
  <li>"13" can be "13" or "13 "</li>
  </ul>
  
  <p>My regex is at the moment this:</p>
  
  <pre><code>\b([\d](\s*)){1,3}\b
  </code></pre>
  
  <p>The results of this regex are the following: (<code>.</code> = blank for better visibility)</p>
  
  <pre><code>123.
  12....
  67.
  89.
  0....
  2
  </code></pre>
  
  <p>But I need this: (. = blank for better visibility)</p>
  
  <pre><code>123
  12.
  67.
  89.
  0..
  2
  </code></pre>
  
  <p>How can I tell the regex engine to count the blanks into the {1,3} option?</p>