题解 | #反转链表#

# -*- coding:utf-8 -*-
# class ListNode:
#     def __init__(self, x):
#         self.val = x
#         self.next = None
class Solution:
    # 返回ListNode
    def ReverseList(self, pHead):
        # write code here
        # 设置一个链表用于返回接收
        res = None
        while pHead != None:
            # 需要一个结点暂时存放pHead的下一个结点，不然会指针丢失
            temp = pHead.next
            # 原来的头结点指向返回结果的结点
            pHead.next = res
            # 都往后挪一位，进行下次循环
            res = pHead
            pHead = temp
        return res