title: how to remove space character between number character?
body: <p>I have string like this:</p>
  
  <pre><code>$str = "old iccid : 809831 3245 345 new iccid : 999000 112221"
  </code></pre>
  
  <p>How to remove the space character between number character in PHP, to become this output?</p>
  
  <pre><code>$output = "old iccid : 8098313245345 new iccid : 999000112221";
  </code></pre>