题解 | #删除链表的倒数第n个节点#
删除链表的倒数第n个节点
https://www.nowcoder.com/practice/f95dcdafbde44b22a6d741baf71653f6
/**
* @author Lu.F
* @version 1.0
* @date 2022/10/7 21:36
*/
public class Solution {
/**
* @param head ListNode类
* @param n int整型
* @return ListNode类
*/
public ListNode removeNthFromEnd(ListNode head, int n) {
// write code here
ListNode slow = head;
ListNode fast = head;
if (head == null) {
return null;
}
// 快指针先走n步
for (int i = 0; i < n; i++) {
fast = fast.next;
}
// 如果走出长度超出n，则删除的为头结点
if (fast == null){
return head.next;
}
// 当fast为null的时候走到末尾，同步向前
while (fast.next != null) {
fast = fast.next;
slow = slow.next;
}
// 删除第n个元素
slow.next = slow.next.next;
return head;
}
}
