title: Add or remove element based on value in number field
body: <p>This is what i have tried so far.
  <div class="snippet" data-lang="js" data-hide="false" data-console="true" data-babel="false">
  <div class="snippet-code">
  <pre class="snippet-code-js lang-js prettyprint-override"><code>$("#add_row").change(function(){
  
      $(".box").append('test &lt;br /&gt;');
  
  });</code></pre>
  <pre class="snippet-code-html lang-html prettyprint-override"><code>&lt;script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"&gt;&lt;/script&gt;
  &lt;input class="form-control input-sm" id="add_row" type="number"&gt;
   
   &lt;div class="box"&gt;&lt;/div&gt;</code></pre>
  </div>
  </div>
  </p>
  
  <p>Now what i want to add or remove the fields based on the number in number field</p>