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import mergeTwoLists from "../merge-two-sorted-lists/index.ts";import { ListNode } from "../reverse-linked-list/ListNode.ts";
export default function mergeKLists(    lists: Array<ListNode | null>,): ListNode | null {    const listsnotnull = lists.filter((a) => !!a) as Array<ListNode>;
    if (listsnotnull.length === 0) return null;    if (listsnotnull.length === 1) return listsnotnull[0];    if (listsnotnull.length === 2) {        return mergeTwoLists(listsnotnull[0], listsnotnull[1]);    }
    if (listsnotnull.length % 2) {        return mergeTwoLists(            listsnotnull[0],            mergeKLists(listsnotnull.slice(1)),        );    } else {        const half = Math.floor(lists.length / 2) - 1;        return mergeKLists([            mergeKLists(listsnotnull.slice(0, half)),            mergeKLists(listsnotnull.slice(half, half + 2)),            mergeKLists(listsnotnull.slice(half + 2)),        ]);    }}