title: set of sets in C++
body: <p>How to create a set of sets in C++?</p>
  
  <pre><code>set&lt;char&gt; inner1;
  set&lt;char&gt; inner2;
  set&lt; set&lt;char&gt; &gt; outer;
  set&lt; set&lt;char&gt; &gt;:: iterator new_it;
  set&lt;char&gt;::iterator it;
  
  for (int i = 65; i &lt; 70; ++i)
      inner1.insert(i);
  
  for (int i = 70; i &lt; 80; ++i)
      inner2.insert(i);
  
  outer.insert(inner1);
  outer.insert(inner2);
  
  for(new_it=outer.begin();new_it!=outer.end();new_it++)
  {
     for(it=*(new_it);it!=(new_it);)
     {
  
     }
  }
  </code></pre>