title: C# more efficient way of comparing two collections
body: <p>I have two collections</p>
  
  <pre><code>List&lt;Car&gt; currentCars = GetCurrentCars();
  List&lt;Car&gt; newCars = GetNewCars();
  </code></pre>
  
  <p>I don't want to use foreach loop or something because i think there should be much better way of doing this.</p>
  
  <p>I am looking for more efficient way to compare this collections and to get results:</p>
  
  <ol>
  <li>List of cars which are in newCars and not in currentCars </li>
  <li>List of cars which are not in newCars and in currentCars </li>
  </ol>
  
  <p>Type Car has int property Id.</p>
  
  <p>There was an answer, which is already deleted saying 
  What i mean by saying efficient:  less code, less mechanics, and more readable cases</p>
  
  <p>So thinking this way what is the cases i have?</p>
  
  <p>What would be less code, less mechanics, and more readable cases?</p>