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Author: JanaSabuj

second-minimum-node-in-a-binary-tree/second-minimum-node-in-a-binary-tree.cpp

@@ -0,0 +1,26 @@
+/**
+ * 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 findSecondMinimumValue(TreeNode* root) {
+        
+        if(root->left == NULL)
+            return -1;
+        
+        int l = root->left->val == root->val ? findSecondMinimumValue(root->left) : root->left->val;
+        int r = root->right->val == root->val ? findSecondMinimumValue(root->right) : root->right->val;
+        
+        if(l == -1 || r == -1)
+            return max(l, r);
+        return min(l,r);
+    }
+};