From c2cdf9cc0a3a3105fbecdd51fd9346cb664b9940 Mon Sep 17 00:00:00 2001
From: Gyandeep <53125532+iGyandeep@users.noreply.github.com>
Date: Wed, 14 Jun 2023 14:14:09 +0530
Subject: [PATCH] 530. Minimum Absolute Difference in BST.cpp

Company: Google
Problem Link: https://leetcode.com/problems/minimum-absolute-difference-in-bst/description/

Note: Alternate Solution / Approach
---
 530. Minimum Absolute Difference in BST.cpp | 26 ++++++++-------------
 1 file changed, 10 insertions(+), 16 deletions(-)

diff --git a/530. Minimum Absolute Difference in BST.cpp b/530. Minimum Absolute Difference in BST.cpp
index fc63556..8692739 100644
--- a/530. Minimum Absolute Difference in BST.cpp	
+++ b/530. Minimum Absolute Difference in BST.cpp	
@@ -11,28 +11,22 @@
  */
 class Solution {
 public:
-    vector<int> data;
+    int ans = INT_MAX;
 
-    void inOrder(TreeNode* root) {
+    void inOrder(TreeNode* root, TreeNode* &previous) {
         if (root == NULL)
             return;
-        
-        inOrder(root->left);
-        data.push_back(root->val);
-        inOrder(root->right);
+        inOrder(root->left, previous);
+        if (previous != NULL)
+            ans = min(ans, root->val - previous->val);
+        previous = root;
+        inOrder(root->right, previous);
     }
 
     int getMinimumDifference(TreeNode* root) {
-        
-        inOrder(root);
-        int ans = INT_MAX;
-        for (int i=0; i<data.size()-1; i++) {
-            int diff = data[i+1] - data[i];
+        TreeNode* previous = NULL;
+        inOrder(root, previous);
 
-            if (diff < ans)
-                ans = diff;
-        }
-
-        return ans;
+        return ans;        
     }
 };