title: Whats does ~~ mean in javascript?
body: <p>I've been reading through some code and noticed a function:</p>
  
  <pre><code>    randint: function(n) {
          return ~~(Math.random() * n)
      }
  </code></pre>
  
  <p>I know ~ means "not" but how does ~~ change this return statement?</p>