title: Find the nearest/closest value in a sorted List
body: <p>I was wondering if it is possible to find the closest element in a sorted <code>List</code> for a element <strong>that is not</strong> in the list.</p>
  <p>For example if we had the values [1,3,6,7] and we are looking for the element closest to 4, it should return 3, because 3 is the biggest number in the array, that is smaller than 4.</p>
  <p>I hope it makes sense, because English is not my native language.</p>