title: checking for 'null' slots in a object array
body: <p>Hi there
  I have come form the java camp and am trying to do a c++ program </p>
  
  <p>I have an array called Manifest that takes passenger objects</p>
  
  <pre><code>for (int i = 0; i&lt; _totalSeats; i++) 
  {
      if (Manifest[i] != instanceOf Passenger) {
          cout&lt;&lt;"empty"endl;
      }
      else {
          cout&lt;&lt; PassengerToString(i);
      }
  }
  </code></pre>
  
  <p>obviously the 'instanceOf' is a problem in C++, 
  I know is==null doesn't work as there is no such thing as null without being specificly inserted
  but to build a blank passenger objects then insert them in each array slot sounds messy and costly.
  Is there a more elegent way?</p>
  
  <p>thanks</p>