数据结构-单链表交换节点

普通情况的结点交换

temp_pre->next = p;
	p_pre->next = p->next;//key step 
	p->next = temp->next;
	temp->next = p_pre->next;
	p_pre->next = temp;

交换结点时一定要注意那个相邻结点的情况，不然……

----相邻结点使用一般情况

会出现大错误

相邻结点单独处理

temp->next = p->next;
	p->next = temp;
	temp_pre->next = p;

具体代码如下（整体是一个选择排序的算法）

void sort_dec(book* head)
{
          
   
	book* temp_pre=head;
	book* p_pre = head;
	book* ex;
	//选择排序
	for (book* temp = head->next; temp != NULL; temp = temp->next)
	{
          
   
		p_pre = temp;
		for (book* p = temp->next; p != NULL; p = p->next)
		{
          
   
			if (temp->price < p->price)
			{
          
   
				//下面的修改指针的交换方式
				if (temp->next == p)      //temp与p为相邻结点
				{
          
   
					temp->next = p->next;
					p->next = temp;
					temp_pre->next = p;
				}
				else                    //一般情况
				{
          
   
					temp_pre->next = p;
					p_pre->next = p->next;//key step 
					p->next = temp->next;
					temp->next = p_pre->next;
					p_pre->next = temp;
				}

				ex = temp;
				temp = p;
				p = temp;
			}
			p_pre = p;
		}
		temp_pre = temp;
	}
}