【leetcode】19. remove nth node from end of list

public static void (String[] args) {
    ListNode head = new ListNode(1);
    ListNode node = head;
    int i = head.val;
    while(++i<6){
        node.next = new ListNode(i);
        node = node.next;
    }
    node = removeNthFromEnd(head,1);
    while(node!=null){
        System.out.print(node.val+" ");
        node = node.next;
    }
}

public static ListNode removeNthFromEnd(ListNode head, int n) {
    
    //ListNode slow = head,fast = head;
    ListNode start = new ListNode(0);
    start.next = head;
    ListNode slow = start,fast = start;

    //Move fast in front so that the gap between slow and fast becomes n
    for (int i = 0; i <= n; i++) {
        fast = fast.next;
    }
    //Move fast to the end, maintaining the gap
    while(fast!=null){
        slow = slow.next;
        fast = fast.next;
    }
    //删除节点
    slow.next = slow.next.next;

    return start.next;
}