题解 | #判断一个链表是否为回文结构#

# class ListNode:
#     def __init__(self, x):
#         self.val = x
#         self.next = None
#
# 代码中的类名、方法名、参数名已经指定，请勿修改，直接返回方法规定的值即可
#
# 
# @param head ListNode类 the head
# @return bool布尔型
#
class Solution:
    def isPail(self , head: ListNode) -> bool:
        # write code here
        if head is None:
            return True
        stack = []
        h1 = head
        while h1:
            stack.append(h1)
            h1 =h1.next
        while head:
            if head.val != stack.pop().val:
                return False
            else:
                head = head.next
        return True

先入栈，再将出栈元素和链表进行比较，入栈是为了反转元素