剑指offer-18-删除链表的节点-golang

题目：给定单向链表的头指针和一个节点指针，在O(1)时间内删除链表节点。

type Node struct {
	val  int
	next *Node
}

func deleteNode(head *Node, target *Node) *Node {
	if head == nil || head.next == nil {
		return nil
	}
	if head == target {
		return head.next
	}
	p, q := head, head.next
	for q != target {
		p = q
		q = q.next
	}
	p.next = q.next
	q = nil
	return head
}