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class Solution:
    def rotateRight(self, head: Optional[ListNode], k: int) -> Optional[ListNode]:
        if k == 0 or not head or not head.next:
            return head
        n = 1
        cur = head
        while cur.next:
            n += 1
            cur = cur.next

        if (add := n - k % n) == n:
            return head

        cur.next = head
        while add:
            cur = cur.next
            add -= 1

        res = cur.next
        cur.next = None
        return res