/*
struct ListNode {
    int val;
    struct ListNode *next;
    ListNode(int x) : val(x), next(NULL) {}
};*/
class PalindromeList {
public:
    bool chkPalindrome(ListNode* A) 
    {
        //思路1:额外开辟一个数组,把链表拷贝到数组去,再利用左右下标对比是否相等
        int arr[900] = {0};
        int i = 0;
        while(A)
        {
            arr[i] = A->val;
            i++;
            A = A->next;
        }
        int left = 0;
        int right = i-1;
        while(left <= right)
        {
            if(arr[left] == arr[right])
            {
                left++;
                right--;
            }
            else 
            {
                return false;
            }
        }
        return true;
    }
};