Add C++ implementation

Signed-off-by: begeekmyfriend <[email protected]>

Author: begeekmyfriend

0235_lowest_common_ancestor_of_a_binary_search_tree/bst_lca.c

@@ -8,7 +8,7 @@ struct TreeNode {
     struct TreeNode *right;
 };
 
-static struct TreeNode* lowestCommonAncestor(struct TreeNode* root, struct TreeNode* p, struct TreeNode* q)
+struct TreeNode* lowestCommonAncestor(struct TreeNode* root, struct TreeNode* p, struct TreeNode* q)
 {
     if (root == NULL || root->val == p->val || root->val == q->val) {
         return root;

0235_lowest_common_ancestor_of_a_binary_search_tree/bst_lca.cc

@@ -0,0 +1,28 @@
+#include <bits/stdc++.h>
+
+using namespace std;
+
+/**
+ * Definition for a binary tree node.
+ * struct TreeNode {
+ *     int val;
+ *     TreeNode *left;
+ *     TreeNode *right;
+ *     TreeNode(int x) : val(x), left(NULL), right(NULL) {}
+ * };
+ */
+
+class Solution {
+public:
+    TreeNode* lowestCommonAncestor(TreeNode* root, TreeNode* p, TreeNode* q) {
+        if (root == nullptr || root->val == p->val || root->val == q->val) {
+            return root;
+        } else if (root->val < p->val && root->val < q->val) {
+            return lowestCommonAncestor(root->right, p, q);
+        } else if (root->val > p->val && root->val > q->val) {
+            return lowestCommonAncestor(root->left, p, q);
+        } else {
+            return root;
+        }
+    }
+};

0236_lowest_common_ancestor_of_a_binary_tree/bst_lca.c

@@ -9,7 +9,7 @@ struct TreeNode {
     struct TreeNode *right;
 };
 
-static struct TreeNode* lowestCommonAncestor(struct TreeNode* root, struct TreeNode* p, struct TreeNode* q)
+struct TreeNode* lowestCommonAncestor(struct TreeNode* root, struct TreeNode* p, struct TreeNode* q)
 {
     if (root == NULL || root == p || root == q) {
         /* edge cases: if return NULL then no p or q node in this path */

0236_lowest_common_ancestor_of_a_binary_tree/bst_lca.cc

@@ -0,0 +1,28 @@
+#include <bits/stdc++.h>
+
+using namespace std;
+                                                                                                                                                                                                           /**
+ * Definition for a binary tree node.
+ * struct TreeNode {
+ *     int val;
+ *     TreeNode *left;
+ *     TreeNode *right;
+ *     TreeNode(int x) : val(x), left(NULL), right(NULL) {}
+ * };
+ */
+class Solution {
+public:
+    TreeNode* lowestCommonAncestor(TreeNode* root, TreeNode* p, TreeNode* q) {
+        if (root == nullptr || root == p || root == q) {
+            return root;
+        }
+        
+        TreeNode *l = lowestCommonAncestor(root->left, p, q);
+        TreeNode *r = lowestCommonAncestor(root->right, p, q);
+        if (l != nullptr && r != nullptr) {
+            return root;
+        } else {
+            return l != nullptr ? l : r;
+        }
+    }
+};