Remove Nth node from end of the list

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

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

const removeNthFromEnd = function (head, n) {
  if (!head) return head;

  let lead = head;
  let follow = head;

  // if n > len(linked list), this will fail.
  // Always check if n can be greater than the len.
  // If yes, add the check before this condition.
  for (let i = 0; i < n; i++) {
    lead = lead.next;
  }

  // This is important for a case when n == len(linked list)
  // 1 -> 2 -> null, n = 2
  //
  // i = 0; i < n; i++
  //
  // cur
  // 1 -> 2 -> null, beginning of loop
  //
  //      cur
  // 1 -> 2 -> null, after i = 0 cycle runs
  //
  //           cur
  // 1 -> 2 -> null, after i = 1 cycle runs
  //
  // In this case when n == len(linked list), we basically
  // want to remove the first element of the list.
  // so your head becomes head.next
  if (!lead) {
    return head.next;
  }

  while (lead.next) {
    follow = follow.next;
    lead = lead.next;
  }

  follow.next = follow.next.next;
  return head;
};