Given a binary tree root, a node X in the tree is named good if in the path from root to X there are no nodes with a value greater than X.

Return the number of good nodes in the binary tree.

Example 1:

Input: root = [3,1,4,3,null,1,5]

Output: 4

Explanation: Nodes in blue are good.

Root Node (3) is always a good node.

Node 4 -> (3,4) is the maximum value in the path starting from the root.

Node 5 -> (3,4,5) is the maximum value in the path

Node 3 -> (3,1,3) is the maximum value in the path.

/**
 * Example:
 * var ti = TreeNode(5)
 * var v = ti.`val`
 * Definition for a binary tree node.
 * class TreeNode(var `val`: Int) {
 *     var left: TreeNode? = null
 *     var right: TreeNode? = null
 * }
 */
class Solution {
    fun goodNodes(root: TreeNode?): Int {
        if (root == null) {
            return 0
        }
        return findGoodNode(root, root.`val`)
    }

}

private fun findGoodNode(root: TreeNode?, maxValue: Int): Int {
    if (root == null) {
        return 0
    }

    if (root.`val` < maxValue) {
        return findGoodNode(root?.left, maxValue) + findGoodNode(root.right, maxValue)
    } else {
        return 1+ findGoodNode(root?.left, root.`val`) + findGoodNode(root.right, root.`val`)
    }

}