title: Is there a better solution than my regex
body: <p>I've spent quit a bit trying to figure out a problem on <a href="http://regex.sketchengine.co.uk/cgi/ex1.cgi" rel="nofollow">this website</a> and I eventually found an regex that worked for the what I was being asked to do</p>
  
  <p>The exercise is:</p>
  
  <pre><code>Enter a regexp that matches all the items in the first column 
  (positive examples) but none of those in the second (negative examples). 
  When you press "submit", you will see what matched.
  
  Positive    Negative
  pit         pt
  spot        Pot
  spate       peat
  slap two    part
  respite
  </code></pre>
  
  <p>The answer that I found was</p>
  
  <pre><code>^\w?.*p[a-z ?]t\w?.*$
  </code></pre>
  
  <p>What I had found out was that all positive words had something of the form <code>p_t</code>.</p>
  
  <p>I matched that with <code>p[a-z ?]t</code> and then <code>^\w?.*</code> is the match any letters preceding <code>p</code> and <code>\w?.*$</code> is to match any alphanumeric characters after <code>t</code></p>
  
  <p>What I want to know is there a better way to answer this? </p>