LeetCode:Remove Nth Node From End of List

题目链接：https://leetcode.com/problems/remove-nth-node-from-end-of-list/description/

题目介绍：删除链表倒数第n个结点

解题思路：先遍历一边链表得出该链表的长度，然后计算倒数第n个结点前的结点个数，然后删除链表倒数第n个结点。

代码如下：

class Solution {public:    ListNode* removeNthFromEnd(ListNode* head, int n) {        int len = 0;        ListNode* node = head;        while (node != NULL) {            node = node->next;            len++;        }        int f = len-n-1;        if (f < 0) {             head = head->next;         } else {            ListNode* a = head;            while (f > 0) {                a = a->next;                f--;            }            a->next = a->next->next;        }        return head;    }};