title: How to update std::map after using the find method?
body: <p>How to update the value of a key in <code>std::map</code> after using the <code>find</code> method?</p>
  
  <p>I have a map and iterator declaration like this:</p>
  
  <pre><code>map &lt;char, int&gt; m1;
  map &lt;char, int&gt;::iterator m1_it;
  typedef pair &lt;char, int&gt; count_pair;
  </code></pre>
  
  <p>I'm using the map to store the number of occurrences of a character. </p>
  
  <p>I'm using Visual C++ 2010.</p>