单链表

#include <stdio.h>
#include <malloc.h>

typedef int T;

typedef struct Node {
T data;
Node* next;
}*node;
typedef struct Node *LinkList;

LinkList InitList()//初始化链表
{
LinkList List = (LinkList)malloc(sizeof(Node));
if (List == NULL)
return NULL;
List->data = 0;
List->next = NULL;
return List;
}

bool Is_Empty(LinkList L)//判空
{
if (L->next == NULL)
return true;
return false;
}

int ListLength(LinkList L)//链表长度
{
int i = 0;
LinkList p = L->next;
while §
{
i++;
p = p->next;
}
return i;
}

void ClearLink(LinkList L)//清空链表
{
LinkList p, q;
p = L->next;
while §
{
q = p->next;
free§;
p = q;
}
L->next = NULL;
}

bool InterPos(LinkList L, int pos, T val)//插入元素
{
int j = 1;
LinkList p, s;
p = L;
while (p && j < pos)
{
p = p->next;
++j;
}
if (!p || j > pos)
return false;
s = (LinkList)malloc(sizeof(Node));
s->data = val;
s->next = p->next;
p->next = s;
return true;
}

T DeletePos(LinkList L, int pos)//按位置删
{
int i = 1;
LinkList p, q;
T e;
p = L;
while (p->next&&i < pos)
{
p = p->next;
++i;
}
if (!(p->next) || i>pos)
return false;
q = p->next;
p->next = q->next;
e = q->data;
free(q);
return e;
}

T DeleteHead(LinkList head)//头删
{
LinkList p = head->next;
T e;
head->next = p->next;
e = p->data;
free§;
return e;
}

T DeleteTail(LinkList L)//尾删
{
LinkList p = NULL;
T e;
while (L->next->next != NULL)
{
L = L->next;
}
p = L->next;
L->next = NULL;
e = p->data;
free§;
return e;
}

bool ChangeVal(LinkList L, int pos, T val)//修改元素
{
if (!(L))
return false;
for (int i = 0; i < pos; i++)
{
if (L == NULL)
return false;
L = L->next;
}
L->data = val;

return true;

}

T GetVal(LinkList L, int pos)//获取元素
{
int i = 1;
LinkList p = L->next;
while (p&&i < pos)
{
p = p->next;
++i;
}
if (!p || i>pos)
return false;
return p->data;
}

int GetPos(LinkList L, T val)//获取元素位置，没有返回0
{
int i = 0;
LinkList p = L->next;
while §
{
i++;
if (p->data == val)
return i;
p = p->next;
}
return 0;
}

LinkList CreateListHead(LinkList Head, int n)//头插法创建表
{
Head = (LinkList)malloc(sizeof(Node));
LinkList node = NULL;
Head->data = 0;
Head->next = NULL;
node = Head->next;

for (int i = 0; i < n; i++)
{
	node = (LinkList)malloc(sizeof(Node));
	node->data = i + 1;
	node->next = Head->next;
	Head->next = node;
}
return Head;

}

LinkList CreatListTail(LinkList Head, int n)//尾插法创建表
{
Head = (LinkList)malloc(sizeof(Node));
LinkList node = NULL;
LinkList end = NULL;
Head->next = NULL;
end = Head;
for (int i = 0; i < n; i++)
{
node = (LinkList)malloc(sizeof(Node));
node->data = i + 1;
end->next = node;
end = node;
}
end->next = NULL;
return Head;
}

void Show(LinkList L)//遍历表中元素
{
LinkList p = L->next;
while §
{
printf("%d “, p->data);
p = p->next;
}
printf(”\n");
}

int main()
{
LinkList L = NULL;
L = CreateListHead(L, 10);
//printf("%d\n", L->data);
//Show(L);
InterPos(L, 5, 100);
Show(L);
printf("%d\n",DeleteTail(L));
Show(L);
//printf("%d\n", ListLength(L));
ClearLink(L);
return 0;
}