title: Length of the longest element in a list
body: <p>I have a list which looks like this:</p>
  
  <pre><code>[[1]]
  [1] -3
  
  [[2]]
  [1] 0 0
  
  [[3]]
  [1]   6 -36  54
  </code></pre>
  
  <p>I want to create a vector from this which looks like </p>
  
  <pre><code>3 -36 54
  </code></pre>
  
  <p>To do this I have considered to add zeroes at the end of the elements, just enough to make the elements of equal size and to use   </p>
  
  <pre><code>Reduce('+',....)
  </code></pre>
  
  <p>to paste the elements together. However, I do not want to add a superfluous amount of zeroes. The list mentioned is not necessary the list for which I want this. I have multiple lists. Finally my question is: Is there a way to retrieve the largest length of the element from a list?</p>