function defaultimport { default } from "https://deno.land/x/masx200_leetcode_test@8.1.5/liang-ge-lian-biao-de-di-yi-ge-gong-gong-jie-dian-lcof/index.ts"; default(headA: ListNode | null, headB: ListNode | null): ListNode | nullParametersheadA: ListNode | nullheadB: ListNode | nullReturnsListNode | null