title: What happens when I subtract an unsigned integer from a signed integer in C++?
body: <p>What happens if I do something like this:</p>
  
  <pre><code>unsigned int u;
  int s;
  
  ...
  s -= u;
  </code></pre>
  
  <p>What's the expected behavior of this:</p>
  
  <p>1) Assuming that the unsigned integer isn't too big to fit in the signed integer?</p>
  
  <p>2) Assuming that the unsigned integer would overflow the signed integer?</p>
  
  <p>Thanks.</p>