Merge pull request #2367 from HQWQF/master

Update 0024.两两交换链表中的节点.md 修复没有delete dummyHead的错误

problems/0024.两两交换链表中的节点.md

@@ -63,7 +63,9 @@ public:
 
             cur = cur->next->next; // cur移动两位，准备下一轮交换
         }
-        return dummyHead->next;
+        ListNode* result = dummyHead->next;
+        delete dummyHead;
+        return result;
     }
 };
 ```