How can I add the corresponding elements of several lists of numbers?
<p>I have some lists of numbers:</p>

<pre><code>[1, 2, 3, 4, 5]
[2, 3, 4, 5, 6]
[3, 4, 5, 6, 7]
</code></pre>

<p>How can I add these lists' elements, assuming that all of the lists that I'm using are the same length? </p>

<p>Here's the kind of output I'd like to get from doing this to the above lists.</p>

<pre><code>[6, 9, 12, 15, 18]
</code></pre>

<p>I know that I'll need a loop of some kind - but how can I do it elegantly?</p>
