2641.js

/** ------------------------------------------------------------------------------
 * 
 * 2641. Cousins in Binary Tree II
 * Topics: Dfs, Binary Tree
 * https://leetcode.com/problems/cousins-in-binary-tree-ii/description/?envType=daily-question&envId=2024-10-23
 * 
 ------------------------------------------------------------------------------ */
/**
 * 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
 * @return {TreeNode}
 */
var replaceValueInTree = function (root) {
  let sum = root.left ? root.left.val : 0
  sum += root.right ? root.right.val : 0
  let queue = [[root, sum]]

  while (queue.length) {
    const nextQueue = []
    const cur = sum

    for (let i = 0; i < queue.length; i++) {
      const node = queue[i][0]
      const sub = queue[i][1]

      node.val = cur - sub
      let next = node.left ? node.left.val : 0
      next += node.right ? node.right.val : 0
      sum += next

      if (node.left) nextQueue.push([node.left, next])
      if (node.right) nextQueue.push([node.right, next])
    }
    sum -= cur
    queue = nextQueue
  }
  return root
}

console.log()