Update 0701.二叉搜索树中的插入操作.md

problems/0701.二叉搜索树中的插入操作.md

@@ -641,6 +641,42 @@ object Solution {
 }
 ```
 
+### rust
+
+迭代：
+
+```rust
+impl Solution {
+    pub fn insert_into_bst(
+        root: Option<Rc<RefCell<TreeNode>>>,
+        val: i32,
+    ) -> Option<Rc<RefCell<TreeNode>>> {
+        if root.is_none() {
+            return Some(Rc::new(RefCell::new(TreeNode::new(val))));
+        }
+        let mut cur = root.clone();
+        let mut pre = None;
+        while let Some(node) = cur.clone() {
+            pre = cur;
+            if node.borrow().val > val {
+                cur = node.borrow().left.clone();
+            } else {
+                cur = node.borrow().right.clone();
+            };
+        }
+        let r = Some(Rc::new(RefCell::new(TreeNode::new(val))));
+        let mut p = pre.as_ref().unwrap().borrow_mut();
+        if val < p.val {
+            p.left = r;
+        } else {
+            p.right = r;
+        }
+
+        root
+    }
+}
+```
+
 
 <p align="center">
 <a href="https://programmercarl.com/other/kstar.html" target="_blank">