title: How can I recast a CNF expression to 3-CNF?
body: <p>I have a CNF expression like this and I want recast it to 3-CNF:</p>
  
  <pre><code>(a+b+c+d)(~a)(~b+d)(a+b+~d)
  </code></pre>
  
  <p>Does anyone know how I can do that?</p>