title: Nested Dictionary/Array in C++
body: <p>Everybody,
  I am a Python/C# guy and I am trying to learn C++.
  In Python I used to do things like:<br>
      <code>myRoutes = {0:[1,2,3], 1:[[1,2],[3,4]], 2:[[1,2,3],[[1,2,3],[1,2,3]],[4]]}</code></p>
  
  <p>Basically when you have arrays of variable length and you don't want to wast a 2D matrix for them, nesting arrays into a dictionary to keep track of them is a good option.</p>
  
  <p>In C++ I tried <code>std::map&lt;int, std:map&lt;int, std:map&lt;int, int&gt; &gt; &gt;</code> and it works but I feel there got to bo a better way to do this.</p>
  
  <p>I prefer to stick to the standard libraries but popular libraries like boost are also acceptable for me. </p>
  
  <p>I appreciate your help,<br>
  Ali</p>