package q61

type ListNode struct {
	Val  int
	Next *ListNode
}

func rotateRight(head *ListNode, k int) *ListNode {
	if head == nil {
		return nil
	}
	n := 1
	p := head
	for p.Next != nil {
		p = p.Next
		n++
	}
	tail := p

	k %= n
	if k == 0 {
		return head
	}

	tail.Next = head
	p = head
	for range n - k - 1 {
		p = p.Next
	}
	newHead := p.Next
	p.Next = nil
	return newHead
}

var _ = rotateRight