Update 0024.两两交换链表中的节点.md

problems/0024.两两交换链表中的节点.md

@@ -405,5 +405,26 @@ impl Solution {
 }
 ```
 
+```rust
+// 递归
+impl Solution {
+    pub fn swap_pairs(head: Option<Box<ListNode>>) -> Option<Box<ListNode>> {
+        if head == None || head.as_ref().unwrap().next == None {
+            return head;
+        }
+
+        let mut node = head.unwrap();
+
+        if let Some(mut next) = node.next.take() {
+            node.next = Solution::swap_pairs(next.next);
+            next.next = Some(node);
+            Some(next)
+        } else {
+            Some(node)
+        }
+    }
+}
+```
+
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