Remove Nth Node From End of List

Leetcode 19.

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/**
 * Definition for singly-linked list.
 * 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 temp = head; 
       int length = 0; 
       while(temp != null){
           temp = temp.next; 
           length++;
       }
       int stop = length - n; 
       ListNode newOne = head;
       //remove the first node
       if(stop == 0){
          head = head.next;
       }
       while(stop > 0){
        if(stop > 1){
           newOne = newOne.next;
         }else{   
           //remove the the nth node from the end of the list  
           newOne.next = newOne.next.next;  
        }  
        stop--;       
       }
     return head; 
    }
}