title: Using Haskell's map function to calculate the sum of a list
body: <p><strong>Haskell</strong></p>
  
  <pre><code>addm::[Int]-&gt;Int
  addm (x:xs) = sum(x:xs)
  </code></pre>
  
  <p>I was able to achieve to get a sum of a list using <code>sum</code> function but is it possible to get the sum of a list using <code>map</code> function?  Also what the use of map function?</p>