19\. Remove Nth Node From End of List

Medium

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

**Example 1:**

![](https://assets.leetcode.com/uploads/2020/10/03/remove_ex1.jpg)

**Input:** head = [1,2,3,4,5], n = 2

**Output:** [1,2,3,5] 

**Example 2:**

**Input:** head = [1], n = 1

**Output:** [] 

**Example 3:**

**Input:** head = [1,2], n = 1

**Output:** [1] 

**Constraints:**

*   The number of nodes in the list is `sz`.
*   `1 <= sz <= 30`
*   `0 <= Node.val <= 100`
*   `1 <= n <= sz`

**Follow up:** Could you do this in one pass?