title: How to match the numeric value in a regular expression?
body: <p>Okay, this is quite an interesting challenge I have got myself into.</p>
  
  <p>My RegEx takes as input lines like the following:</p>
  
  <pre>
  147.63.23.156/159
  94.182.23.55/56
  134.56.33.11/12
  </pre>
  
  <p>I need it to output a regular expression <em>that matches the range represented.</em> Let me explain.</p>
  
  <p>For example, if the RegEx receives <code>147.63.23.156/159</code>, then it needs to output a RegEx that matches the following:</p>
  
  <pre>
  147.63.23.156
  147.63.23.157
  147.63.23.158
  147.63.23.159
  </pre>
  
  <p>How can I do this?</p>
  
  <p>Currently I have:</p>
  
  <pre><code>(\d{1,3}\.\d{1,3}\.\d{1,3}\.)(\d{1,3})/(\d{1,3})
  </code></pre>
  
  <ul>
  <li>$1 contains the first <code>xxx.xxx.xxx.</code> part</li>
  <li>$2 contains the lower range for the number</li>
  <li>$3 contains the upper range for the number</li>
  </ul>