一、题目

1、合并两个数组

class Solution:def merge(self, nums1: List[int], m: int, nums2: List[int], n: int) -> None:nums1[m:] = nums2nums1.sort()

2、判断链表中是否有环

class Solution:def hasCycle(self, head: ListNode) -> bool:seen = set()while head:if head in seen:return Trueseen.add(head)head = head.nextreturn False

3、反转链表

# Definition for singly-linked list.
# class ListNode:
#     def __init__(self, val=0, next=None):
#         self.val = val
#         self.next = next
class Solution:def reverseList(self, head: Optional[ListNode]) -> Optional[ListNode]:cur=headpre=Nonewhile cur:nnext = cur.nextcur.next = prepre = curcur = nnextreturn pre

 

二、问答

1、数组和链表的区别