title: Merge of sorted and unsorted linked lists in java implementation
body: <p>I was reading about sorted linked lists and unsorted sorted lists ... I found this table <a href="http://bigocheatsheet.com/" rel="nofollow">http://bigocheatsheet.com/</a> </p>
  
  <p>I do not understand what they mean by saying in the third table that a sorted linked list has Merge of <code>O(m+n)</code> while an unsorted sorted list has Merge of <code>O(1)</code>!</p>
  
  <p>What does that mean?</p>
  
  <p>thanks</p>