剑指 Offer 06. 从尾到头打印链表

# Definition for singly-linked list.
class ListNode:
    def __init__(self, x):
        self.val = x
        self.next = None
class Solution:
    # 自己写的，调用insert，比较费时间。
    # def reversePrint(self, head: ListNode) -> List[int]:
    #     lis = []
    #     while head:
    #         lis.insert(0, head.val)
    #         head = head.next
    #     return lis
    # 大佬写的，用append然后，直接切片逆序输出，这样的话速度更快
    #  字符串[开始索引:结束索引:步长]
    def reversePrint(self, head: ListNode) -> List[int]:
        stack = []
        while head:
            stack.append(head.val)
            head = head.next
        return stack[::-1]