Grokking 238

class Solution {
    public ListNode removeNthFromEnd(ListNode head, int n) {

        ListNode start = new ListNode(-1);
        ListNode slow = start;
        ListNode fast = start;
        slow.next = head;

        for (int i = 0; i < n + 1; i++) {
            fast = fast.next;
        }

        while (fast != null) {
            slow = slow.next;
            fast = fast.next;
        }

        slow.next = slow.next.next;
        return start.next;
    }
}