title: C++ 3 level map
body: <p>I am using a multilevel map</p>
  
  <pre><code>map&lt;string, map&lt;string, map&lt;string, int&gt;&gt;&gt; _myMap;
  </code></pre>
  
  <p>How to access the integer value using the iterator of outermost map only?</p>
  
  <p>Please help me in finding suitable references for 3-level map too.</p>