/** * Definition for singly-linked list. * public class ListNode { * int val; * ListNode next; * ListNode(int x) { val = x; } * } */ public class Solution { public ListNode removeNthFromEnd(ListNode head, int n) { if(head == null) return null; ListNode fast = head; while(n>0){ fast = fast.next; n--; } if(fast == null) return head.next; ListNode slow = head; while(fast.next != null){ slow = slow.next; fast = fast.next; } slow.next = slow.next.next; return head; } }