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:
    bool chkPalindrome(ListNode* A) {
        struct ListNode* slow=A;
        struct ListNode* fast=A;
        stack<int> s;
        while(fast && fast->next)
        {
            s.push(slow->val);
            slow=slow->next;
            fast=fast->next->next;
        }
        if(fast)//偶数不为空
            slow=slow->next;
        while(slow)
        {
            if(s.top()!=slow->val)
            {
                return false;
            }
            s.pop();
            slow=slow->next;
        }
        return true;
    }
};