Kth Smallest Element in BST solution Updated

Kth_Smallest_Element_in_BST.cpp

@@ -0,0 +1,26 @@
+class Solution {
+public:
+    int solve(TreeNode* root, int &i, int k){
+        //base case
+        if(root == NULL){
+            return -1;
+        }
+
+        int left = solve(root -> left, i, k);
+        if(left != -1){
+            return left;
+        }
+
+        i++;
+        if(i == k){
+            return root -> val;
+        }
+        return solve(root -> right, i, k);
+    }
+
+    int kthSmallest(TreeNode* root, int k) {
+        int i = 0;
+        int ans = solve(root, i, k);
+        return ans;
+    }
+};