添加（0235.二叉搜索树的最近公共祖先.md）：增加typescript版本

problems/0235.二叉搜索树的最近公共祖先.md

@@ -350,6 +350,39 @@ var lowestCommonAncestor = function(root, p, q) {
 };
 ```
 
+## TypeScript
+
+> 递归法：
+
+```typescript
+function lowestCommonAncestor(root: TreeNode | null, p: TreeNode | null, q: TreeNode | null): TreeNode | null {
+    if (root.val > p.val && root.val > q.val)
+        return lowestCommonAncestor(root.left, p, q);
+    if (root.val < p.val && root.val < q.val)
+        return lowestCommonAncestor(root.right, p, q);
+    return root;
+};
+```
+
+> 迭代法：
+
+```typescript
+function lowestCommonAncestor(root: TreeNode | null, p: TreeNode | null, q: TreeNode | null): TreeNode | null {
+    while (root !== null) {
+        if (root.val > p.val && root.val > q.val) {
+            root = root.left;
+        } else if (root.val < p.val && root.val < q.val) {
+            root = root.right;
+        } else {
+            return root;
+        };
+    };
+    return null;
+};
+```
+
+
+
 
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