Given the root of a binary tree, imagine yourself standing on the right side of it. Return the values of the nodes you can see ordered from top to bottom.

Example 1:

Input:  1 2 3 null 5 null 4
Output: 1 3 4

Example 2:

Input:  1 null 3
Output: 1 3

Constraints:

• The number of nodes in the tree is in the range [0, 100]
• -100 ≤ Node.val ≤ 100

Input format: BFS level-order, space-separated, null for missing nodes.

Output format: Space-separated integers — the right side view.