2583.js

/** ------------------------------------------------------------------------------
 * 
 * 2583. Kth Largest Sum in a Binary Tree
 * Topics: Bfs, Tree
 * https://leetcode.com/problems/kth-largest-sum-in-a-binary-tree/?envType=daily-question&envId=2024-10-22
 * 
 ------------------------------------------------------------------------------ */
/**
 * Definition for a binary tree node.
 * function TreeNode(val, left, right) {
 *     this.val = (val===undefined ? 0 : val)
 *     this.left = (left===undefined ? null : left)
 *     this.right = (right===undefined ? null : right)
 * }
 */
/**
 * @param {TreeNode} root
 * @param {number} k
 * @return {number}
 */
var kthLargestLevelSum = function (root, k) {
  var result = []
  var traverse = (node, level = 0) => {
    if (!node) return null

    if (result[level] == null) result[level] = node.val
    else result[level] += node.val

    traverse(node.left, level + 1)
    traverse(node.right, level + 1)
  }

  traverse(root)
  if (!result[k - 1]) return -1
  return result.sort((a, b) => b - a)[k - 1]
}