题解 | 判断一个链表是否为回文结构 -双指针 +数组

# 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 not head:
            return False 
        arr=[]
        cur =head
        while cur: 
            arr.append(cur.val)
            cur=cur.next
        
        left =0 
        right=len(arr)-1
        while left <=right:
            if arr[left]!=arr[right]:
                return False
            left+=1
            right-=1
        return True