title: Holding unordered_map element to a pointer/iterator
body: <p>Each time to find an element I use <code>find</code> and thus, I have a pointer returned to it (iterator would be better to describe it rather than pointer). But, in the case the element is not there, I go create it.</p>
  
  <p>The problem is that after both cases I want to have something that will point to that element no matter if it existed or not (because I ensured that I created it). My solution is to use find (for the second time, which I guess is costly), but I think that there could be a unified way to hold a reference to the item without doing a second search (either by previous find or while creating the item).</p>
  
  <p>Is this possible?</p>