title: C# equivalent of C++ map<string,double>
body: <p>I want to keep some totals for different accounts. In C++ I'd use STL like this:</p>
  
  <pre><code>map&lt;string,double&gt; accounts;
  
  // Add some amounts to some accounts.
  accounts["Fred"] += 4.56;
  accounts["George"] += 1.00;
  accounts["Fred"] += 1.00;
  
  cout &lt;&lt; "Fred owes me $" &lt;&lt; accounts['Fred'] &lt;&lt; endl;
  </code></pre>
  
  <p>Now, how would I do the same thing in C# ?</p>