牛客题霸 NC23 划分链表

Posted 2021-09-09 Starzkg

https://www.nowcoder.com/practice/1dc1036be38f45f19000e48abe00b12f

解决方案

Go

func partition(head *ListNode, x int) *ListNode {
	// write code here
	return solve(head, nil, nil, x)
}

func solve(head *ListNode, pre *ListNode, h *ListNode, x int) *ListNode {
	if head == nil {
		return h
	}
	if head.Val >= x {
		if pre == nil {
			return solve(head.Next, head, head, x)
		} else {
			next := head.Next
			pre.Next = head
			head.Next = nil
			return solve(next, head, h, x)
		}
	} else {
		head.Next = solve(head.Next, pre, h, x)
		return head
	}
}

参考文章