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import { TreeNode } from "../binary-tree-inorder-traversal/TreeNode.ts";
export function serialize(root: TreeNode | null): string {    if (!root) {        return "null";    }
    return JSON.stringify(TreeNodeToArray(root)).replaceAll("null", "");}type TreeNodeArray =    | null    | [number, TreeNodeArray, TreeNodeArray]    | number    | [number, TreeNodeArray];function TreeNodeToArray(root: TreeNode | null): TreeNodeArray {    if (!root) return null;    if (!root.left && !root.right) {        return root.val;    }    if (root.left && !root.right) {        return [root.val, TreeNodeToArray(root.left)];    }    return [root.val, TreeNodeToArray(root.left), TreeNodeToArray(root.right)];}function ArrayToTreeNode(array: TreeNodeArray): TreeNode | null {    // console.log('array',array)    if (array === null) return null;    if (Array.isArray(array) && array.length === 3) {        return new TreeNode(            array[0],            ArrayToTreeNode(array[1]),            ArrayToTreeNode(array[2]),        );    }    if (Array.isArray(array) && array.length === 2) {        return new TreeNode(array[0], ArrayToTreeNode(array[1]));    }    if (typeof array === "number") {        return new TreeNode(array);    }    throw new Error("not array length 3 or 2:" + array);}export function deserialize(data: string): TreeNode | null {    if (data === "null") {        return null;    }    const array = JSON.parse(        data.replaceAll(",,", ",null,"),        // .replaceAll(",]", ",null]"),    );    return ArrayToTreeNode(array);}