/**
 * Definition for singly-linked list.
 * struct ListNode {
 *     int val;
 *     ListNode *next;
 *     ListNode(int x) : val(x), next(NULL) {}
 * };
 */
class Solution {
public:
    vector<int> res;
    vector<int> printListReversingly(ListNode* head) {
        if (!head) {
            return {};
        }

        printListReversingly(head -> next);
        res.push_back(head -> val);
        return res;
    }
};