title: Binary tree level order traversal time complexity
body: <p><a href="http://www.geeksforgeeks.org/level-order-tree-traversal/" rel="nofollow">HERE</a> it is explained that method 1 of level order traversal has a time complexity of O(n^2). Can someone please explain me this. I am not sure how author is saying that printGivenLevel() takes O(n).</p>
  
  <p>"Time Complexity: O(n^2) in worst case. For a skewed tree, printGivenLevel() takes O(n) time where n is the number of nodes in the skewed tree. So time complexity of printLevelOrder() is O(n) + O(n-1) + O(n-2) + .. + O(1) which is O(n^2)."</p>
  
  <p>On the contrary <a href="http://leetcode.com/2010/09/binary-tree-level-order-traversal-using_17.html" rel="nofollow">HERE</a>, it seems to be proved that it is O(n)</p>