title: Rust mutable value vs mutable reference
body: <p>What is the difference between </p>
  
  <pre><code>let y = &amp;mut 5;
  *y += 1;
  let x = *y + 1;
  </code></pre>
  
  <p>and</p>
  
  <pre><code>let mut y = 5;
  y += 1;
  let x = y + 1;
  </code></pre>
  
  <p>They return the same result via <code>println!</code>, but I can't decide which one is preferable.</p>