title: Sum the content of 2 list in Groovy
body: <p>I have two lists in Groovy and need to sum the contents of both.</p>
  
  <p>For example:</p>
  
  <pre><code>list1 = [1,1,1]
  list2 = [1,1,1]
  </code></pre>
  
  <p>I expected this result:</p>
  
  <pre><code>total = [2,2,2]
  </code></pre>
  
  <hr>
  
  <p>I try to sum with + operator o .sum method, but I have a concatenation of the lists.</p>
  
  <pre><code>[1, 1, 1, 1, 1, 1]
  </code></pre>
  
  <p>It's Groovy enough groovy or I need to loop each element of the lists?</p>