title: Calculate the availavable time based on the properties in the object
body: <p>I have this kind of json.</p>
  <pre><code>var meetings = [
    {
      id: '1',
      start_time: &quot;2020-11-15T08:30:00+00:00&quot;,
      end_time: &quot;2020-11-15T14:15:00+00:00&quot;
    },
    {
      id: '2',
      start_time: &quot;2020-11-15T19:30:00+00:00&quot;,
      end_time: &quot;2020-11-15T20:30:00+00:00&quot;
    },
  ];
  </code></pre>
  <p>So two meetings first one: 08:30 - 14:15 second: 19:30-20:30</p>
  <p>There are 24 availavable hours for working so:</p>
  <pre><code>start_time = '00:00:00';
  end_time = '23:59:00';
  </code></pre>
  <p>but in the format that i need would be</p>
  <pre><code>var start_time = '2020-11-15T00:00:00+00:00';
  var end_time = '2020-11-15T23:59:00+00:00';
  </code></pre>
  <p>How can i calculate the avalavable hours depening on the already maked meetings? So because the first meeting is from 08:30 - 14:15 and the second 19:30-20:30 i will need json with the following result with the available hours:</p>
  <pre><code>[
    {
      start_time:'2020-11-15T00:00:00+00:00',
      end_time:'2020-11-15T08:30:00+00:00'
    },
  
    {
      start_time:'2020-11-15T14:15:00+00:00',
      end_time:'2020-11-15T19:30:00+00:00'
    },
  
    {
      start_time:'2020-11-15T20:30:00+00:00',
      end_time:'2020-11-15T23:59:00+00:00'
    }
  ]
  </code></pre>