Remove Nth Node From End of List

Given a linked list, remove the nth node from the end of list and return its head.

public class Solution {
    public ListNode removeNthFromEnd(ListNode head, int n) {
        ListNode safe = new ListNode(-1);
        safe.next = head;
        ListNode p1 = safe;
        for(int i=0;i<=n;i++){
            p1 = p1.next;
        }
        ListNode p2 = safe;
        while(p1!=null){
            p1 = p1.next;
            p2 = p2.next;
        }
        p2.next=p2.next.next;
        return safe.next;
    }
}