fastest way to add elements in list in R
<pre><code>zii=list()
zii[[1]]=c(1,2,3)
zii[[2]]=c(1,2,3)
zii[[3]]=c(1,2,3)
</code></pre>

<p>What is the best way to perform element-wise addition in the list , IE:
<code>sum=c(1+1+1,2+2+2,3+3+3)=c(3,6,9)</code>
I tried <code>Reduce("+",zii)</code> and it is slow. Any other suggestions ?</p>