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import { TreeNode } from "../binary-tree-inorder-traversal/TreeNode.ts";
function reverseOddLevels(root: TreeNode | null): TreeNode | null {    if (!root) return null;    let depth = 0;    level([root], (nodes) => {        if (depth & 1) {            nodes.map((a) => a.val).reverse().forEach((v, i) =>                nodes[i].val = v            );        }        depth++;    });    return root;}export default reverseOddLevels;export function level(nodes: TreeNode[], output: (r: TreeNode[]) => void) {    if (nodes.length === 0) return;
    output(nodes);
    level(        nodes            .map((n) => [n.left, n.right].filter(Boolean) as TreeNode[])            .flat(),        output,    );}