title: What does the following code do?
body: <p>I was wondering what the following code does:</p>
  
  <pre><code>for (auto x:m) std::cout &lt;&lt; x &lt;&lt; " ";
  </code></pre>
  
  <p>I already know that <code>auto</code> is a way to leave it to the compiler to decide the type of the variable but I don't know what <code>:m</code> does.</p>