<li>Use the <code>List.map</code> function with the <code>Value</code> function to create a list of integers from the option type values.
          <li>Sum the resulting list.<li>
          </li>
        </ol>

<p><a href="#" onclick="toggleCode(this,'arrays');return false;" class="uiitem">Show Code</a>
      <div class="indent-large" id="arrays" style="display:none;">
<pre class="prettyprint">
   |> List.filter (fun x -> x.IsSome)
   |> List.map (fun x -> x.Value)
   |> List.sum
</pre></div></p>

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