试编写一个在循环双向链表中进行删除操作的算法，要求删除的结点是指定结点p的前趋结点（自己创建链表）

Answer 1

要删除p节点的前驱，先定义一个节点q为p的前驱节点。有如下关系：
q->pre->next=p;
p->pre=q->pre;
然后删除q节点就可以了。

# include <iostream.h>
# include <assert.h>

template <class Type>
struct DbNode
{
Type data;
DbNode<Type> *next,*pre;

DbNode(DbNode<Type> *ptr1 = NULL,DbNode<Type> *ptr2 = NULL):next(ptr1),pre(ptr2)
{}
DbNode(Type x,DbNode<Type> *ptr1 = NULL,DbNode<Type> *ptr2 = NULL):data(x),next(ptr1),pre(ptr2)
{}
};

template <class Type>
class DbList
{
public:
DbList()
{
head = new DbNode<Type>;
head->pre = head->next = head;
}

DbList(const DbList<Type> &dl)
{ }

~DbList()
{
Destory();
}
public:
void DeleteNode(DBNode<Type> *p)
{
DBNode<Type> *q=p->pre;

q->pre->next=p;
p->pre=q->pre;
delete q;
}

private:
DbNode<Type> *head;

void Destory()
{
DbNode<Type> *p = head->next;
while(p != head)
{
head->next = p->next;
p->next->pre = head;
delete p;
p = head->next;
}
}
};

追问

帮忙编个c的呗

Answer 2

这么简单的问题，老师上课应该有讲的吧

Answer 3

。。。。

追问

？？？？