title: Accessing std::map keys and values
body: <p>How do you access an <code>std::vector</code> of the keys or values of an <code>std::map</code>?</p>
  
  <p>Thanks.</p>
  
  <p>Edit: I would like to access the actual elements, not just copies of their contents. essentially I want a reference, not a copy.</p>
  
  <p>This is essentially what I am wanting to do:</p>
  
  <pre><code>std::map&lt;std::string, GLuint&gt; textures_map;
  
  // fill map
  
  glGenTextures( textures_map.size(), &amp;textures_map.access_values_somehow[0] );
  </code></pre>