From 1aa2db8bba31ba6be39a065cd2bd3465f1811964 Mon Sep 17 00:00:00 2001
From: SOHAM-GADEKAR <sohamg.3456@gmail.com>
Date: Mon, 20 Oct 2025 11:36:53 +0530
Subject: [PATCH] Added Solution of LeetCode Problem No. 230

---
 .../Programs/C/LeetCode/Q230.c                | 94 +++++++++++++++++++
 1 file changed, 94 insertions(+)
 create mode 100644 Domains/CompetitiveProgramming/Programs/C/LeetCode/Q230.c

diff --git a/Domains/CompetitiveProgramming/Programs/C/LeetCode/Q230.c b/Domains/CompetitiveProgramming/Programs/C/LeetCode/Q230.c
new file mode 100644
index 00000000..9d958d1b
--- /dev/null
+++ b/Domains/CompetitiveProgramming/Programs/C/LeetCode/Q230.c
@@ -0,0 +1,94 @@
+/*
+===============================================================
+230. Kth Smallest Element in a BST
+===============================================================
+
+Difficulty: Medium
+Tags: Binary Search Tree, Depth-First Search, Tree, Binary Tree
+
+---------------------------------------------------------------
+Problem Statement:
+---------------------------------------------------------------
+Given the root of a binary search tree (BST) and an integer k,
+return the kth smallest value (1-indexed) among all the values
+of the nodes in the tree.
+
+---------------------------------------------------------------
+Example 1:
+---------------------------------------------------------------
+Input: root = [3,1,4,null,2], k = 1
+Output: 1
+
+Explanation:
+The in-order traversal of the BST is [1, 2, 3, 4].
+The 1st smallest element is 1.
+
+---------------------------------------------------------------
+Example 2:
+---------------------------------------------------------------
+Input: root = [5,3,6,2,4,null,null,1], k = 3
+Output: 3
+
+Explanation:
+The in-order traversal of the BST is [1, 2, 3, 4, 5, 6].
+The 3rd smallest element is 3.
+
+---------------------------------------------------------------
+Constraints:
+---------------------------------------------------------------
+- The number of nodes in the tree is n.
+- 1 <= k <= n <= 10^4
+- 0 <= Node.val <= 10^4
+
+---------------------------------------------------------------
+Hint:
+---------------------------------------------------------------
+- The in-order traversal of a BST gives the elements
+  in sorted order.
+- You can stop traversing early once you reach the kth element.
+===============================================================
+*/
+
+/**
+ * Definition for a binary tree node.
+ * struct TreeNode {
+ *     int val;
+ *     struct TreeNode *left;
+ *     struct TreeNode *right;
+ * };
+ */
+
+/**
+ * Function: inorder
+ * -----------------
+ * Performs an in-order traversal of the BST to find the kth smallest element.
+ * 
+ * @param p     : Pointer to the current node in the BST.
+ * @param k     : The target position (kth smallest element to find).
+ * @param temp  : Temporary variable to store the current result.
+ * 
+ * @return      : The kth smallest value if found, otherwise returns temp.
+ */
+
+ 
+int inorder(struct TreeNode* p, int k, int temp)
+{
+    // Base case: if the current node is NULL, simply return temp
+    if (p != NULL)
+    {
+        // Traverse the left subtree first (smallest elements come first in BST)
+        temp = inorder(p->left, k - 1, temp);
+
+        // If k reaches 0, we have found the kth smallest node
+        if (k == 0)
+        {
+            return p->val;
+        }
+
+        // Continue traversal in the right subtree
+        temp = inorder(p->right, k - 1, temp);
+    }
+
+    // Return the temporary result if kth element is not found yet
+    return temp;
+}