* name :单向循环链表
* author :[email protected]
* data :2024/04/23
* function :设计一个单向循环链表,实现头插、尾插、中间插、头删、尾删、中间删
* noto :None
*
* CopyRight (c) 2023-2024 [email protected] A1l Right Reseverd
*
****************************************/
//指的是单向循环链表中的结点有效数据类型,用户可以根据需要进行修改
typedef int DataType_t;
//构造单向循环链表的结点,链表中所有结点的数据类型应该是相同的
typedef struct CircularLinkedList
{
DataType_t data; //结点的数据域
struct LinkedList *next; //结点的指针域
}CircLList_t;
//创建一个空单向循环链表,空链表应该有一个头结点,对链表进行初始化
CircLList_t * CircLList_Create(void)
{
//1.创建一个头结点并对头结点申请内存
CircLList_t *Head = (CircLList_t *)calloc(1,sizeof(CircLList_t));
if (NULL == Head)
{
perror("Calloc memory for Head is Failed");
exit(-1);
}
//2.对头结点进行初始化,头结点是不存储数据域,指针域指向自身,体现“循环”思想
Head->next = Head;
//3.把头结点的地址返回即可
return Head;
}
//创建新的结点,并对新结点进行初始化(数据域 + 指针域)
CircLList_t * CircLList_NewNode(DataType_t data)
{
//1.创建一个新结点并对新结点申请内存
CircLList_t *New = (CircLList_t *)calloc(1,sizeof(CircLList_t));
if (NULL == New)
{
perror("Calloc memory for NewNode is Failed");
return NULL;
}
//2.对新结点的数据域和指针域进行初始化
New->data = data;
New->next = NULL;
return New;
}
//头插
bool CircLList_HeadInsert(CircLList_t *Head,DataType_t data)
{
CircLList_t *Phead = Head;//备份头结点的地址
//1.创建新的结点,并对新结点进行初始化
CircLList_t *New = CircLList_NewNode(data);
if(NULL == New)
{
printf("can not new node\n");
return false;
}
//2.判断链表是否为空,如果为空,则把新结点作为首结点,体现“循环”
if(Head->next == Head)
{
Head->next = New;
New->next = New;
return true;
}
//3.如果链表是非空的,则需要对链表尾结点的next指针进行处理,指向首结点
//要遍历了,备份头结点地址
while(Phead->next)
{
Phead = Phead->next;
if(Phead->next == Head->next)
{
break;
}
}
Phead->next = New;//尾结点的next指针指向新的首结点
New->next = Head->next;//新结点的next指针指向原来的首结点
Head->next = New;//更新首结点地址,让头结点的next指针指向新结点
return true;
}
//尾插
bool CircLList_TailInsert(CircLList_t *Head,DataType_t data)
{
CircLList_t *Phead = Head;//备份头结点的地址
//1.创建新的结点,并对新结点进行初始化
CircLList_t *New = CircLList_NewNode(data);
if(NULL == New)
{
printf("can not new node\n");
return false;
}
//2.判断链表是否为空,如果为空,则把新结点作为首结点,体现“循环”
if(Head->next == Head)
{
Head->next = New;
New->next = New;
return true;
}
//3.如果链表是非空的,则需要对链表尾结点的next指针进行处理,指向首结点
//要遍历了,备份头结点地址
while(Phead->next)
{
Phead = Phead->next;
if(Phead->next == Head->next)
{
break;
}
}
Phead->next = New;//旧的尾结点的next指针指向新结点
New->next = Head->next;//新结点的next指针指向首结点地址
return ture;
}
//指定位置插入--myself
bool CircLList_DestInsert(CircLList_t *Head,DataType_t destval,DataType_t data)
{
CircLList_t *Phead = Head;//备份头结点的地址
//1.创建新的结点,并对新结点进行初始化
CircLList_t *New = CircLList_NewNode(data);
if(NULL == New)
{
printf("can not new node\n");
return false;
}
//2.判断链表是否为空,如果为空,则把新结点作为首结点,体现“循环”
if(Head->next == Head)
{
Head->next = New;
New->next = New;
return true;
}
//3.如果链表是非空的,则需要对链表尾结点的next指针进行处理,指向首结点
//要遍历了,备份头结点地址
while(Phead->next)
{
Phead = Phead->next;
if(Phead->next == Head->next)
{
break;
}
}
}
//遍历链表
bool CircLList_Print(CircLList_t *Head)
{
//对单向循环链表的头结点的地址进行备份
CircLList_t *Phead = Head;
//判断当前链表是否为空,为空则直接退出
if (Head->next == Head)
{
printf("current linkeflist is empty!\n");
return false;
}
//从首结点开始遍历
while(Phead->next)
{
//把头结点的直接后继作为新的头结点
Phead = Phead->next;
//输出头结点的直接后继的数据域
printf("data = %d\n",Phead->data);
//判断是否到达尾结点,尾结点的next指针是指向首结点的地址
if (Phead->next == Head->next)
{
break;
}
}
return true;
}
//头删
bool LList_HeadDel(LList_t *Head)
{
//对单向循环链表的头结点的地址进行备份
CircLList_t *Phead = Head;
//对单向循环链表的首结点的地址进行备份
CircLList_t *Temp = Head->next;
//2.判断链表是否为空,如果为空,则退出
if(Head->next == Head)
{
printf("linkedlist is Empty\n");
return true;
}
//3.判断链表中是否只有首结点
if(Head->next == Head->next->next)
{
Temp->next = NULL;//首结点的next指针指向NULL
Head->next = Head;//头结点的next指针指向头结点,体现“循环”
free(Temp); //释放首结点
return ture;
}
//4.如果链表是非空的,则需要对链表尾结点的next指针进行处理,指向新的首结点
while(Phead->next)
{
Phead = Phead->next;
if(Phead->next == Head->next)
{
break;
}
}
Phead->next = Head->next->next;//让尾结点的next指针指向新的首结点
Head->next = Phead->next;//更新首结点,让头结点的next指针指向新的首结点
Temp->next = NULL;//旧的首结点的next指针指向NULL,从链表中断开
free(Temp);
return ture;
}
标签:结点,单向,Head,CircLList,next,链表,中间,Phead
From: https://www.cnblogs.com/CamelliaWY/p/18158633