How to total values in a List<t> where key values are the same
<p>I have a List that looks like this</p>

<pre><code>List&lt;custom&gt; this_list = new List&lt;custom&gt;();

this_list.Add(new custom()
{
  key = male,
  value = 50
});

this_list.Add(new custom()
{
  key = female,
  value = 90
});

this_list.Add(new custom()
{
  key = male,
  value = 5
});
</code></pre>

<p>How would I be able to evaluate this list so I can determine that there are 55 males and 90 females? Also, let's suppose that my keyset is very large and it would be inefficient to manually define male or female or another key.  How would I create a new list containing the combined totals and unique keys? </p>

<p>Thanks for any help and attention!</p>
