//不带头结点的单链表

#include

#include

//链表结构体

typedef struct _Node

{

int val;

struct _Node* next;

}Node,*LinkList;

void InitList(LinkList* list)

{

*list = NULL;

}

void InsertHeadList(LinkList* list)

{

int data;

scanf("%d", &data);

while (data != 0)

{

Node* node = (Node*)malloc(sizeof(Node));

node->val = data;

if (*list == NULL)

{

*list = node;

(*list)->next = NULL;

}

else

{

node->next = *list;

*list = node;

}

scanf("%d", &data);

}

}

void Print(LinkList list)

{

Node* s = list;

while (s != NULL)

{

printf("%d ", s->val);

s = s->next;

}

printf("\n");

}

void InsertTailList(LinkList* list)

{

int data;

scanf("%d", &data);

while (data != 0)

{

Node* node = (Node*)malloc(sizeof(Node));

node->val = data;

node->next = NULL;

if (*list == NULL)

{

*list = node;

}

else

{

Node* s = *list;

while (s->next != NULL)

{

s = s->next;

}

s->next = node;

}

scanf("%d", &data);

}

}

void DeleteHeadList(LinkList* list)

{

if (*list == NULL)

{

return;

}

Node* s = *list;

*list = (*list)->next;

free(s);

}

void DeleteTailList(LinkList* list)

{

if (*list == NULL)

{

return;

}

Node* s = *list;

if (s->next == NULL)

{

DeleteHeadList(list);

}

while (s->next->next != NULL)

{

s = s->next;

}

Node* r = s->next;

s->next = s->next->next;

free(r);

}

int Count(LinkList list)

{

Node* s = list;

int count = 0;

while (s != NULL)

{

s = s->next;

count++;

}

return count;

}

bool IsEmpty(LinkList list)

{

if (list != NULL)

{

return false;

}

return true;

}

void Clear(LinkList* list)

{

while (*list != NULL)

{

DeleteHeadList(list);

}

}

void Reverse(LinkList* list)

{

if (*list == NULL || (*list)->next == NULL)

{

return;

}

//三节点法

Node* first;

Node* second;

Node* last;

first = *list;

second = (*list)->next;

last = second->next;

first->next = NULL;

//如果有三个节点以上开始转置

while (last != NULL)

{

//连接

second->next = first;

//后移

first = second;

second = last;

last = last->next;

}

second->next = first;

*list = second;

}

int main(void)

{

LinkList list;

//初始化

InitList(&list);

//插入

//头插

//InsertHeadList(&list);

//尾插

InsertTailList(&list);

//统计节点个数

int ncount = Count(list);

printf("ncount=%d\n", ncount);

//单链表原地转置

Reverse(&list);

//打印

Print(list);

//删除

//头删

DeleteHeadList(&list);

//尾删

DeleteTailList(&list);

Print(list);

//判断是否为空

bool temp = IsEmpty(list);

if (temp)

{

printf("空\n");

}

else

{

printf("不是空\n");

}

//清空

Clear(&list);

temp = IsEmpty(list);

if (temp)

{

printf("空\n");

}

else

{

printf("不是空\n");

}

return 0;

}