title: C++ - iterate over map of maps
body: <p>I would like to ask how can I iterate over map of maps. I do have this map -  <code>std::map &lt;string, std::map &lt;string, double&gt; &gt; myMap</code> and I would like to iterate through it like in a 2D array. I am little bit familiar with the iterators, but I haven't iterated through a 2D map before.</p>
  
  <p>I do currently have one for cycle with my iterator, but I have no idea how to iterate over the second map. Can you give me some hints ?</p>
  
  <p>Thank you for your answers</p>