title: std::map initialization with a std::vector
body: <p>I want to initialize a <code>std::map</code> object with keys contained in a <code>std::vector</code> object.</p>
  
  <pre><code>std::vector&lt;char&gt; mykeys { 'a', 'b', 'c' ];
  std::map&lt;char, int&gt; myMap;
  </code></pre>
  
  <p>How can I do that without a loop?</p>
  
  <p>And can I add a default value to my <code>int</code>?</p>