> For the complete documentation index, see [llms.txt](https://jaywin.gitbook.io/leetcode/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://jaywin.gitbook.io/leetcode/solutions/1485-clone-binary-tree-with-random-pointer.md). # 1485. Clone Binary Tree With Random Pointer ## Description A binary tree is given such that each node contains an additional random pointer which could point to any node in the tree or null. Return a [**deep copy**](https://en.wikipedia.org/wiki/Object_copying#Deep_copy) of the tree. The tree is represented in the same input/output way as normal binary trees where each node is represented as a pair of `[val, random_index]` where: * `val`: an integer representing `Node.val` * `random_index`: the index of the node (in the input) where the random pointer points to, or `null` if it does not point to any node. You will be given the tree in class `Node` and you should return the cloned tree in class `NodeCopy`. `NodeCopy` class is just a clone of `Node` class with the same attributes and constructors. **Example 1:** ![](https://assets.leetcode.com/uploads/2020/06/17/clone_1.png) ``` **Input:** root = [[1,null],null,[4,3],[7,0]] **Output:** [[1,null],null,[4,3],[7,0]] **Explanation:** The original binary tree is [1,null,4,7]. The random pointer of node one is null, so it is represented as [1, null]. The random pointer of node 4 is node 7, so it is represented as [4, 3] where 3 is the index of node 7 in the array representing the tree. The random pointer of node 7 is node 1, so it is represented as [7, 0] where 0 is the index of node 1 in the array representing the tree. ``` **Example 2:** ![](https://assets.leetcode.com/uploads/2020/06/17/clone_2.png) ``` **Input:** root = [[1,4],null,[1,0],null,[1,5],[1,5]] **Output:** [[1,4],null,[1,0],null,[1,5],[1,5]] **Explanation:** The random pointer of a node can be the node itself. ``` **Example 3:** ![](https://assets.leetcode.com/uploads/2020/06/17/clone_3.png) ``` **Input:** root = [[1,6],[2,5],[3,4],[4,3],[5,2],[6,1],[7,0]] **Output:** [[1,6],[2,5],[3,4],[4,3],[5,2],[6,1],[7,0]] ``` **Example 4:** ``` **Input:** root = [] **Output:** [] ``` **Example 5:** ``` **Input:** root = [[1,null],null,[2,null],null,[1,null]] **Output:** [[1,null],null,[2,null],null,[1,null]] ``` **Constraints:** * The number of nodes in the `tree` is in the range `[0, 1000].` * Each node's value is between `[1, 10^6]`. ## ac ```java ``` --- # Agent Instructions This documentation is published with GitBook. GitBook is the documentation platform designed so that both humans and AI agents can read, navigate, and reason over technical content effectively. Learn more at gitbook.com. ## Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question. Perform an HTTP GET request on the current page URL with the `ask` query parameter, and the optional `goal` query parameter: ``` GET https://jaywin.gitbook.io/leetcode/solutions/1485-clone-binary-tree-with-random-pointer.md?ask=&goal= ``` `ask` is the immediate question: it should be specific, self-contained, and written in natural language. `goal` is optional and describes the broader end goal you are ultimately trying to accomplish on behalf of the user. GitBook uses it to tailor the answer towards what is most useful for that goal. The response will contain a direct answer to the question and relevant excerpts and sources from the documentation. Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.