双向链表（带头结点）

带头结点双向链表的内存分布情况

---

头文件

#pragma once
//双向链表
typedef struct DNode
{
	int data;
	DNode* next;
	DNode* prio;
}DNode , *DList ;

//初始化
void InitList(DList plist);

//头插法
bool Insert_head(DList plist,int val);

//尾插法
bool Insert_tail(DList plist,int val);

//在pos下标插入数据val
bool Insert_pos(DList plist,int pos,int val);

//查找，找到返回节点地址，没有找到返回NULL
DNode *Search(DList plist,int key);

//删除第一个key对应的节点
bool Delete(DList plist,int key);

//删除第一个数据节点，并通过rtval获得删除的值
bool Delete_head(DList plist,int *rtval);

//删除最后一个数据节点，并通过rtval获得删除的值
bool Delete_tail(DList plist,int *rtval);

//获取长度，统计数据节点的个数
int GetLength(DList plist);

//判空
bool IsEmpty(DList plist);

//清除所以数据
void Clear(DList plist);

//销毁所有节点
void Destroy(DList plist);

//打印
void Show(DList plist);


//反转
void Reverse(DList plist);

---

cpp文件

#include
#include
#include"dlist.h"
#include
//初始化
void InitList(DList plist)
{
	assert(plist != NULL);
	if(plist == NULL)
	{
		return ;
	}
	plist->next = NULL;
	plist->prio = NULL;
}
static DNode *BuyNode(int val)
{
	DNode* p = (DNode*) malloc (sizeof(DNode));
	p->data = val;
	return p;
}

//头插法
bool Insert_head(DList plist,int val)
{
	DNode * p = BuyNode(val);

	assert(plist != NULL);
	if(plist  == NULL)
	{
		return false;
	}
	if(plist->next != NULL)
	{
		plist->next->prio = p;
	}
	p->prio = plist;
	p->next = plist ->next;
	plist->next = p;

	return true;
}

//尾插法
bool Insert_tail(DList plist,int val)
{
	DNode * p = BuyNode(val);

	assert(plist != NULL);
	if(plist  == NULL)
	{
		return false;
	}
	DNode *q;
	for(q = plist;q->next!= NULL;q = q->next);
	//将p 插在q 的后面
	q->next =p;
	p->prio =q;
	p->next = NULL;

	return true;
}

//在pos下标插入数据val
bool Insert_pos(DList plist,int pos,int val)
{
	DNode * p = BuyNode(val);

	assert(plist != NULL);
	if(plist  == NULL)
	{
		return false;
	}
	DNode *q;
	int i = 0;
	for( q =plist->next; q!= NULL && inext);
	if(i < 0)
	{
		return false;
	}
	p->next = q->next;
	p->prio = q;
	q->next = p;
	return true;
}

//查找，找到返回节点地址，没有找到返回NULL
DNode *Search(DList plist,int key)
{
	assert(plist != NULL);
	if(plist == NULL)
	{
		return false;
	}
	for(DNode *p = plist->next;p != NULL;p = p->next)
	{
		if(p->data == key)
		{
			return p;
		}
	}
	return NULL;

}

//删除第一个key对应的节点
bool Delete(DList plist,int key)
{
	assert(plist != NULL);
	if(plist == NULL)
	{
		return false;
	}
	DNode * p =Search(plist,key);
	if(p == NULL)
	{
		return false;
	}
	p->prio->next = p->next;
	if(p->next != NULL)
	{
		p->next->prio = p->prio;
	}
	free(p);

	return true;

}

//删除第一个数据节点，并通过rtval获得删除的值
bool Delete_head(DList plist,int *rtval)
{
	assert(plist != NULL);
	if(plist != NULL || plist->next == NULL)
	{
		return false;
	}
	if(rtval != NULL)
	{
		*rtval = plist->data;
	}
	DNode *p = plist->next;
	plist->next = p->next;
	p->next ->prio = plist;
	free(p);
	return true;
}

//删除最后一个数据节点，并通过rtval获得删除的值
bool Delete_tail(DList plist,int *rtval)
{
	assert(plist != NULL);
	if(plist == NULL || plist->next == NULL)
	{
		return false;
	}
	DNode *p = plist ;
	DNode *q;
	for(q = plist; q->next != NULL;q = q->next);
	q->next = p;
	if(rtval != NULL)
	{
		*rtval = p->data;
	}
	q->next = NULL;
	free(p);
	return true;
}

//获取长度，统计数据节点的个数
int GetLength(DList plist)
{
	 int length = 0;
    for(DNode *p=plist->next;p!=NULL;p=p->next)
    {
	length++;
    }
    return length;
}

//判空
bool IsEmpty(DList plist)
{
	return plist->next == NULL;
}

//清除所有数据
void Clear(DList plist)
{
	Destroy(plist);
}

//销毁所有节点
void Destroy(DList plist)
{
	 DNode *p;
    while(plist->next != NULL)
    {
	p = plist->next;
	plist->next = p->next;
	free(p);
	}
}

//打印
void Show(DList plist)
{
	 for(DNode *p=plist->next;p!=NULL;p=p->next)
    {
		printf("%d ",p->data);
    }
    printf("\n");
}



//反转
void Reverse(DList plist)
{
	DNode * q;
	DNode * p  = plist->next;
	while(p != NULL)
	{
		q = p;
		p = p->next;
		q->next = plist ->next;
		plist ->next = p;
	}

}

---

主函数

#include
#include
#include"dlist.h"
int main()
{
	DNode dlist;
	InitList(&dlist);
	for(int i=0;i<10;i++)
	{
		Insert_head(&dlist,i);
	}
	Show(&dlist);

	Reverse(&dlist);
	Show(&dlist);
	return 0;
}