Create 1448-count-good-nodes-in-binary-tree.js

Author: everthis

1448-count-good-nodes-in-binary-tree.js

@@ -0,0 +1,31 @@
+/**
+ * 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}
+ */
+const goodNodes = function(root) {
+  if(root == null) return 0
+  let res = 0
+
+  helper(root, root.val)
+
+  return res
+  
+  function helper(node, max) {
+    if(node == null) return
+    if(node.val >= max) {
+      res++
+      max = node.val
+    }
+    helper(node.left, max)
+    helper(node.right, max)
+  }
+};