Palindrome Linked List leetcode

Given a singly linked list, determine if it is a palindrome.

Follow up:
Could you do it in O(n) time and O(1) space?

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思路：
1.利用快慢两个指针找到中间结点
2.从中间结点下一个结点开始逆置链表，得到新的链表
3.新的链表与原来链表依次比较结点，如有不同，return false

思路很清晰，代码直接写在leetcode网站上了，没有调试，一次性AC通过，很有成就感

bool isPalindrome(ListNode* head) {
if (head == nullptr || head->next == nullptr)
return true;
// 寻找中间结点
ListNode *slow = head;
ListNode *fast = head;
while (fast->next != nullptr && fast->next->next != nullptr)
{
slow = slow->next;
fast = fast->next->next;
}
// 逆置后部分链表
ListNode *newList = slow->next;
ListNode *curNode = slow->next->next;
newList->next = nullptr;
while (curNode != nullptr)
{
ListNode *temp = curNode->next;
curNode->next = newList;
newList = curNode;
curNode = temp;
}
// 依次比较
while (newList != nullptr)
{
if (newList->val != head->val)
return false;
newList = newList->next;
head = head->next;
}
return true;
}