title: What is the actual name of a "random key dictionary" structure?
body: <p>I need a data structure like a dictionary, but I don't care about the keys used. I just want to use the key as a handle, to recognize the item, so I'd like to let the structure choose it.</p>
  
  <p>Example:</p>
  
  <pre><code>RandomKeyDict dict;
  Key k = dict.insert(foobar);
  ...
  // somewhere else in the code
  dict.get(k);
  </code></pre>
  
  <p>How is this structure actually called?</p>
  
  <p>edit: I don't think that <code>vector</code> is my guy here, because I also need to remove items from the structure.</p>