Create count-nodes-equal-to-average-of-subtree.cpp

Author: gabedonnan

count-nodes-equal-to-average-of-subtree.cpp

@@ -0,0 +1,40 @@
+/**
+ * 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 {
+private:
+    int counter = 0;
+public:
+    std::pair<int, int> subtreeSum(TreeNode* root) {
+        int current_sum = root->val;
+        int current_size = 1;
+        if (root->left != NULL) {
+            auto [subtree_size_l, subtree_sum_l] = subtreeSum(root->left);
+            current_sum += subtree_sum_l;
+            current_size += subtree_size_l;
+        }
+        if (root->right != NULL) {
+           auto [subtree_size_r, subtree_sum_r] = subtreeSum(root->right);
+            current_sum += subtree_sum_r;
+            current_size += subtree_size_r;
+        }
+        
+        if (current_sum / current_size == root->val) {
+            counter += 1;
+        }
+
+        return std::make_pair(current_size, current_sum);
+    }
+    int averageOfSubtree(TreeNode* root) {
+        subtreeSum(root);
+        return counter;
+    }
+};