Update to match video's code

Problem: 0098-validate-binary-search-tree
Language: C++
Submission URL: https://leetcode.com/problems/validate-binary-search-tree/submissions/883304020/

Author: caba5

cpp/0098-validate-binary-search-tree.cpp

@@ -7,6 +7,17 @@
     Space: O(n)
 */
 
+/**
+ * Definition for a binary tree node.
+ * struct TreeNode {
+ *     int val;
+ *     TreeNode *left;
+ *     TreeNode *right;
+ *     TreeNode() : val(0), left(nullptr), right(nullptr) {}
+ *     TreeNode(int x) : val(x), left(nullptr), right(nullptr) {}
+ *     TreeNode(int x, TreeNode *left, TreeNode *right) : val(x), left(left), right(right) {}
+ * };
+ */
 /**
  * Definition for a binary tree node.
  * struct TreeNode {
@@ -19,6 +30,22 @@
  * };
  */
 class Solution {
+public:
+    bool isValidBST(TreeNode* root) {
+        return helper(root, LONG_MIN, LONG_MAX);
+    }
+private:
+    bool helper(TreeNode* root, long left, long right){
+        if (!root)
+            return true;
+        if (root->val < right && root->val > left){
+            return helper(root->left, left, root->val) && helper(root->right, root->val, right);
+        }
+        return false;
+    }
+};
+/*
+class Solution {
 public:
     bool isValidBST(TreeNode* root) {
         TreeNode* prev = NULL;
@@ -46,6 +73,7 @@ class Solution {
         return true;
     }
 };
+*/
 
 // class Solution {
 // public: