title: Check if integer contains digit javascript
body: <p>How do you check whether or not an integer contains a digit?</p>
  
  <p>For example:</p>
  
  <pre><code>var n = 12;
  var m = 34;
  
  n contains 1 // true
  m contains 1 // false
  </code></pre>
  
  <p>What's the fastest (performance wise) way to do this without turning the integer into a string? </p>