题解 | #链表的回文结构#

/*
struct ListNode {
    int val;
    struct ListNode *next;
    ListNode(int x) : val(x), next(NULL) {}
};*/
class PalindromeList {
public:
struct ListNode* middleNode(struct ListNode* head)
{
    struct ListNode* slow=head,*fast =head;
    while(fast &&fast->next)
    {
        slow=slow->next;
        fast=fast->next;
    }
    return slow;
}
struct ListNode* reverseList(struct ListNode* head)
{
    struct ListNode* cur=head;
    struct ListNode* newhead=NULL;
    while(cur)
    {
        struct ListNode* next=cur->next;
        cur->next=newhead;
        newhead=cur;
        cur=next;
    }
    return newhead;
}
    bool chkPalindrome(ListNode* A) {
        // write code here
        struct ListNode* mid=middleNode(A);
        struct ListNode* rmid=reverseList(mid);
        while(rmid && A)
        {
            if(rmid->val !=A->val)
            return false;
            rmid=rmid->next;
            A=A->next;
        }
        return true;
    }
};