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import reverse_Linked_List from "../reverse-linked-list/index.ts";import { ListNode } from "../reverse-linked-list/ListNode.ts";import { get_deep_next_of_list } from "./get_deep_next_of_list.ts";import { get_length_of_list } from "./get_length_of_list.ts";
export default function reverseBetween(    head: ListNode | null,    left: number,    right: number,): ListNode | null {    if (!head) return head;    if (!head.next) return head;    if (left === right) return head;
    const length = get_length_of_list(head);    if (left === 1 && length === right) {        return reverse_Linked_List(head);    }
    if (left !== 1) {        return new ListNode(            head.val,            reverseBetween(head.next, left - 1, right - 1),        );    }    const start = get_deep_next_of_list(head, left - 1);    const end = get_deep_next_of_list(head, right - 1);    const succ = get_deep_next_of_list(head, right - 1).next;    const reverse = new WeakMap<ListNode, ListNode>();    const pre_start = get_deep_next_of_list(head, left - 1 - 1);
    for (let l: null | ListNode = start; l !== end; l = l.next) {        if (!l) break;        if (l.next) {            reverse.set(l.next, l);        }    }    pre_start.next = end;    start.next = succ;    let cur = end;    let next = reverse.get(cur);    while (next) {        cur.next = next;
        cur = next;        next = reverse.get(cur);    }    if (left === 1) {        return end;    } else {        return head;    }}