title: How do I use a PriorityQueue?
body: <p>How do I get a <a href="https://docs.oracle.com/javase/8/docs/api/java/util/PriorityQueue.html" rel="noreferrer"><code>PriorityQueue</code></a> to sort on what I want it to sort on?</p>
  
  <p>Also, is there a difference between the <a href="https://docs.oracle.com/javase/8/docs/api/java/util/PriorityQueue.html#offer-E-" rel="noreferrer"><code>offer</code></a> and <a href="https://docs.oracle.com/javase/8/docs/api/java/util/PriorityQueue.html#add-E-" rel="noreferrer"><code>add</code></a> methods?</p>