Binary Tree Right Side View

Standing on the right side, you see node 1 at level 0, node 3 at level 1 (it's rightmost), and node 4 at level 2 (it's rightmost even though it's a child of node 3).

At each level, you see the rightmost node: 1, then 3, then 4 (left child of 2, but rightmost at that level since 3 has no children at that depth), then 5.

The tree only has right children, so you see both nodes from the right side.

An empty tree has no nodes to see.