Consider the following algorithm for doing a postorder

/in /by

 

Consider the following algorithm for doing a postorder traversal of a binary tree with root vertex root.

Postorder(root)

if root != null then

Postorder(root.left);

Postorder(root.right);

visit root;

end if;

Prove that this algorithm runs in time Θ(n) when the input is an n-vertex binary tree.