https://leetcode-cn.com/problems/linked-list-cycle-ii/

    1. /**
    2.  * Definition for singly-linked list.
    3.  * class ListNode {
    4.  *     val: number
    5.  *     next: ListNode | null
    6.  *     constructor(val?: number, next?: ListNode | null) {
    7.  *         this.val = (val===undefined ? 0 : val)
    8.  *         this.next = (next===undefined ? null : next)
    9.  *     }
    10.  * }
    11.  */
    13. function detectCycle(head: ListNode | null): ListNode | null {
    14.   const set = new Set();
    15.   while (head) {
    16.     if (set.has(head)) return head;
    17.     set.add(head);
    18.     head = head.next;
    19.   }
    20.   return null
    21. };

    https://bigfrontend.dev/zh/problem/implement-Promise-any

    function any(promises) {
  promises = Array.isArray(promises) ? promises : [];
  let len = promises.length;
  const errors = [];
  return new Promise((resolve, reject) => {
    if (len === 0) {
      return reject(new AggregateError('No Promise in Promise.any was resolved'))
    }
    promises.forEach((promise, index) => {
      promise.then(value => {
        return resolve(value);
      }, (reason) => {
        len--;
        errors[index] = reason;
      }).finally(() => {
        if (len === 0) {
          reject(new AggregateError('No Promise in Promise.any was resolved', errors))
        }
      })
    });
  })
}