title: Count the number of Enum values in list using Linq
body: <p>I have an enum like this :</p>
  
  <pre><code>public enum PlayResultEnum
  {
      First, Cooperate, Defect
  }
  </code></pre>
  
  <p>I create a list of this:</p>
  
  <pre><code>    public List&lt;PlayResultEnum&gt; Agent1Result=new List&lt;PlayResultEnum&gt;();
      public List&lt;PlayResultEnum&gt; Agent2Result=new List&lt;PlayResultEnum&gt;();
  </code></pre>
  
  <p>I need to count ,for example <strong>First</strong> values in my list using lambda (Linq) .</p>
  
  <p>How can I do that?</p>