Right view of the binary tree

   1
 /
2   3

The right view of this is 1, 3. Similarly consider one more example

            1
          / 
         2    5
        /  
       3   4 
Right view for this tree contains 1, 5, 4.

This is similar to my last post which asks for the left view of the binary tree. We just need to make the following changes to the algorithms discussed in the earlier post.

In case of iterative solution, we need to add the right child first to the queue before adding the left child.

In the recursive approach, we need to first recurse on the right child. Below is the modified code.