题解 | #从尾到头打印链表#

两次遍历，一次统计长度，一次逆序输出。

int* printListFromTailToHead(struct ListNode* listNode, int* returnSize ) {
    int *res;
    struct ListNode* tmp = listNode;
    int n = 0;
    while (tmp) {
        n++;
        tmp = tmp->next;
    }
    printf("%i", n);
    *returnSize = n;
    res = (int*)malloc(sizeof(int) * n);
    for (int i = n - 1; i >= 0; i--) {
        res[i] = listNode->val;
        // printf("%i", listNode->val);
        listNode = listNode->next;
    }
    return res;
    // write code here
}