typedef int status;
typedef char ElemType;
typedef struct Node
{
	ElemType data;
	struct Node* next;
}Node,*LinkList;

void init_linklist(LinkList *l)/*對單鏈表進行初始化*/
{
	*l=(LinkList)malloc(sizeof(Node)); 
	(*l)->next=NULL;
}

void CreateList(LinkList L)
{
	Node *r,*s;
	int flag=1;
	char c;
	r = L;
    printf("\nplease input the value of the list element:");
	while(flag)
	{
		c=getchar();
		if(c!='$')
		{
			s=(Node*)malloc(sizeof(Node));
			if(!s) exit(OVERFLOW);
			s->data=c;
			r->next=s;
			r=s;
		}
		else 
		{ 
			flag=0;
			r->next=NULL;
		}
	}/*end of while*/
}/*end of CreateList*/

status InsList (LinkList L,int i,ElemType e)
{ 
	Node *pre,*s;
	int k;
	pre=L;
	k=0;
	while(pre&&k<i-1)
	{pre=pre->next;
	k++;
	}
	if(!pre)
	{
		printf("The position of insert is invalid!");
		return (ERROR);
	}
	s=(Node*)malloc(sizeof(Node));
	if(!s) exit(OVERFLOW);
	s->data=e;
	s->next=pre->next;
	pre->next=s;
	return (OK);
} /*end of InsList*/

status DelList(LinkList L,int i,ElemType *e)
{
	Node *pre,*r;
	int k;
	pre=L;
	k=0;
	while(pre->next!=NULL&&k<i-1)
	{
		pre=pre->next;
		k++;
	}/*end of while*/
	if(!(pre->next))
	{
		printf("the position of delete is invalid!!\n");
		return(ERROR);
	}/*end of if*/
	r=pre->next;
	pre->next=pre->next->next;
	*e=r->data;
	free(r);
	return(OK);
}/*end of DelList*/

status OutputValue(LinkList l)
{
	LinkList p;
	p=l->next;
	if(!p) 
	{
		printf("the list is empty!!\n");
		return ERROR;
	}
	printf("\nthe value of the list is:");
	while(p)
	{
		printf("%c  ",p->data);
		p=p->next;
	}
        printf("\n");
	return OK;
}