LeetCode: Binary Tree Right Side View Solution

Approach

Priority from right to left

Keep track of the current depth to check if node is viewed

Implementation

1/**
2 * Definition for a binary tree node.
3 * function TreeNode(val, left, right) {
4 *     this.val = (val===undefined ? 0 : val)
5 *     this.left = (left===undefined ? null : left)
6 *     this.right = (right===undefined ? null : right)
7 * }
8 */
9/**
10 * @param {TreeNode} root
11 * @return {number[]}
12 */
13var rightSideView = function (root) {
14  const res = []
15  const view = function (node, depth) {
16    if (!node) return
17    if (depth === res.length) {
18      res.push(node.val)
19    }
20    view(node.right, depth + 1)
21    view(node.left, depth + 1)
22  }
23  view(root, 0)
24  return res
25}