# 删除链表的倒数第 N 个结点

<p>给你一个链表，删除链表的倒数第 <code>n</code><em> </em>个结点，并且返回链表的头结点。</p><p><strong>进阶：</strong>你能尝试使用一趟扫描实现吗？</p><p> </p><p><strong>示例 1：</strong></p><img alt="" src="https://img-service.csdnimg.cn/img_convert/3ab1d7132da7283b4578c8df78c8fb67.jpeg" style="width: 542px; height: 222px;" /><pre><strong>输入：</strong>head = [1,2,3,4,5], n = 2<strong><br />输出：</strong>[1,2,3,5]</pre><p><strong>示例 2：</strong></p><pre><strong>输入：</strong>head = [1], n = 1<strong><br />输出：</strong>[]</pre><p><strong>示例 3：</strong></p><pre><strong>输入：</strong>head = [1,2], n = 1<strong><br />输出：</strong>[1]</pre><p> </p><p><strong>提示：</strong></p><ul>	<li>链表中结点的数目为 <code>sz</code></li>	<li><code>1 <= sz <= 30</code></li>	<li><code>0 <= Node.val <= 100</code></li>	<li><code>1 <= n <= sz</code></li></ul>

## template

```java
public class ListNode {
	int val;
	ListNode next;
	ListNode() {
	}
	ListNode(int val) {
		this.val = val;
	}
	ListNode(int val, ListNode next) {
		this.val = val;
		this.next = next;
	}
}
class Solution {
	public ListNode removeNthFromEnd(ListNode head, int n) {
		ListNode v = new ListNode(0, head);
		ListNode handle = v;
		List<ListNode> index = new ArrayList<>();
		while (v != null) {
			index.add(v);
			v = v.next;
		}
		int pre = index.size() - n - 1;
		int next = index.size() - n + 1;
		index.get(pre).next = next >= 0 && next < index.size() ? index.get(next) : null;
		return handle.next;
	}
}
```

## 答案

```java

```

## 选项

### A

```java

```

### B

```java

```

### C

```java

```