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Maximum Difference Between Node and Ancestor

Problem statement​

Given the root of a binary tree, find the maximum value v for which there exist different nodes a and b where v = |a.val - b.val| and a is an ancestor of b.

A node a is an ancestor of b if either: any child of a is equal to b or any child of a is an ancestor of b.

Example 1:

Input: root = [8,3,10,1,6,null,14,null,null,4,7,13]Output: 7Explanation: We have various ancestor-node differences, some of which are given below :|8 - 3| = 5|3 - 7| = 4|8 - 1| = 7|10 - 13| = 3Among all possible differences, the maximum value of 7 is obtained by |8 - 1| = 7.

Example 2:

Input: root = [1,null,2,null,0,3]Output: 3

Constraints:

  • The number of nodes in the tree is in the range [2, 5000].
  • 0 <= Node.val <= 105

My solution​

/**
 * 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 {number}
 */
var maxAncestorDiff = function(root) {
    function traverse(node, max, min) {
        if (!node) {
            return max - min
        }
        
        
        max = Math.max(max, node.val)
        min = Math.min(min, node.val)
        
        return Math.max(
            traverse(node.left, max, min),
            traverse(node.right, max, min),
        )
    }
    
    
    return traverse(root, root.val, root.val)
};