title: how to use scanf unsigned int
body: <p>I have the following</p>
  
  <pre><code> unsigned int value = 12;
   int res = std::sscanf("-567", "%u", &amp;value);
  </code></pre>
  
  <p>When this is run res is 1 indicating 1 match and value is set to 4294966729
  Whereas I was expecting no matches to be made</p>
  
  <p>I would be grateful if someone could explain this behaviour.</p>