🌴 Day 9

Author: AkashRajpurohit

README.md

@@ -9,12 +9,13 @@
 2. [Insertion Sort List](https://leetcode.com/explore/challenge/card/november-leetcoding-challenge/564/week-1-november-1st-november-7th/3517/) ➡️ [CPP Solution](Week1/insertionSortList.cpp)
 3. [Consecutive Characters](https://leetcode.com/explore/challenge/card/november-leetcoding-challenge/564/week-1-november-1st-november-7th/3518/) ➡️ [CPP Solution](Week1/maxPower.cpp)
 4. [Minimum Height Trees](https://leetcode.com/explore/challenge/card/november-leetcoding-challenge/564/week-1-november-1st-november-7th/3519/) ➡️ [CPP Solution](Week1/findMinHeightTrees.cpp)
-5. [Minimum Cost to Move Chips to The Same Position](https://leetcode.com/explore/challenge/card/november-leetcoding-challenge/564/week-1-november-1st-november-7th/3519/) ➡️ [CPP Solution](Week1/minCostToMoveChips.cpp)
-6. [Find the Smallest Divisor Given a Threshold](https://leetcode.com/explore/challenge/card/november-leetcoding-challenge/564/week-1-november-1st-november-7th/3520/) ➡️ [CPP Solution](Week1/smallestDivisor.cpp)
-7. [Add Two Numbers II](https://leetcode.com/explore/challenge/card/november-leetcoding-challenge/564/week-1-november-1st-november-7th/3521/) ➡️ [CPP Solution](Week1/addTwoNumbers.cpp)
+5. [Minimum Cost to Move Chips to The Same Position](https://leetcode.com/explore/challenge/card/november-leetcoding-challenge/564/week-1-november-1st-november-7th/3520/) ➡️ [CPP Solution](Week1/minCostToMoveChips.cpp)
+6. [Find the Smallest Divisor Given a Threshold](https://leetcode.com/explore/challenge/card/november-leetcoding-challenge/564/week-1-november-1st-november-7th/3521/) ➡️ [CPP Solution](Week1/smallestDivisor.cpp)
+7. [Add Two Numbers II](https://leetcode.com/explore/challenge/card/november-leetcoding-challenge/564/week-1-november-1st-november-7th/3522/) ➡️ [CPP Solution](Week1/addTwoNumbers.cpp)
 
 ## Week 2 🚧
 1. [Binary Tree Tilt](https://leetcode.com/explore/challenge/card/november-leetcoding-challenge/565/week-2-november-8th-november-14th/3524/) ➡️ [CPP Solution](Week2/findTilt.cpp)
+2. [Maximum Difference Between Node and Ancestor](https://leetcode.com/explore/challenge/card/november-leetcoding-challenge/565/week-2-november-8th-november-14th/3525/) ➡️ [CPP Solution](Week2/maxAncestorDiff.cpp)
 
 ## Week 3 🚧
 Coming soon...

Week2/maxAncestorDiff.cpp

@@ -0,0 +1,30 @@
+/**
+ * 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) {}
+ * };
+ */
+class Solution {
+public:
+    int result = 0;
+    int maxAncestorDiff(TreeNode* root) {
+        dfs(root, root->val, root->val);
+        return result;
+    }
+    
+    void dfs(TreeNode* root, int currMin, int currMax) {
+        if(root == NULL) return;
+        
+        result = max(result, max(abs(root->val - currMin), abs(root->val - currMax)));
+        currMin = min(currMin, root->val);
+        currMax = max(currMax, root->val);
+        
+        dfs(root->left, currMin, currMax);
+        dfs(root->right, currMin, currMax);
+    }
+};