1. 递归

import sys
sys.setrecursionlimit(10000)  
# 经测试python3解释器默认递归最大深度为3000，所以当链表长度大于3000的时候，会引发RecursionError异常
class Solution:
    def ReverseList(self , head: ListNode) -> ListNode:
        # write code here
        if head is None or head.next is None:
            return head
        next_ = head.next
        reverse = self.ReverseList(next_)
        next_.next = head
        head.next = None
        return reverse

2.遍历翻转

class Solution:
    def ReverseList(self , head: ListNode) -> ListNode:
        # write code here
        new_head = None
        while head:
            tmp = head.next
            head.next = new_head
            new_head = head
            head = tmp
        return new_head