//Author:张佳琪
#include <stdio.h>
#include <stdlib.h>
typedef int ElemType;
typedef struct Node
{
    ElemType data;
    struct Node *next;
}Node,*LinkedList;
LinkedList init()
{
    Node *L;
    L=(Node *)malloc(sizeof(Node));
    if(L==NULL)
        printf("fail\n");
    L->next=L;
    return L;
}
LinkedList create()
{
    Node *L;
    L=init();
    Node *r;
    r=L;
    ElemType x;
    while(scanf("%d",&x))
    {
        if(x==0)
            break;
        Node *p;
        p=(Node *)malloc(sizeof(Node));
        p->data=x;
        r->next=p;
        r=p;
    }
    r->next=L;
    return L;
}
LinkedList insert(LinkedList L,int i,ElemType x)
{
    Node *p;
    p=L;
    int j;
    for(j=1;j<i;j++)
        p=p->next;
    Node *q;
    q=(Node *)malloc(sizeof(Node));
    q->data=x;
    q->next=p->next;
    p->next=q;
    return L;
}
LinkedList deleteelem(LinkedList L,ElemType x)
{
    Node *p,*q;
    p=L;
    while(1)
    {
        if(p->data!=x&&p->next!=L)
        {
            q=p;
            p=p->next;
        }
        else if(p->data!=x&&p->next==L)
        {
            break;
        }
        else if(p->data==x&&p->next!=L)
        {
            q->next=p->next;
            free(p);
            p=q->next;
        }
        else if(p->data==x&&p->next==L)
        {
            q->next=L;
            free(p);
            break;
        }
    }
    return L;
}
LinkedList deletepos(LinkedList L,int i)
{
    Node *p;
    p=L;
    int j;
    if(i!=1)
    {
        for(j=1;j<i;j++)
            p=p->next;
        p->next=p->next->next;
    }
    else
    {
        while(p->next!=L)
        {
            p=p->next;
        }
        L=p->next->next;
        p->next=L;
    }
    return L;
}
void show(LinkedList L)
{
    Node *p;
    p=L->next;
    while(1)
    {
        printf("%d ",p->data);
        if(p->next==L)
            break;
        p=p->next;
    }
    printf("\n");
}
int main()
{
    LinkedList L;
    int i,j;
    while(1)
    {
        printf("----@@@menu@@@----\n");
        printf("1.建立\n");
        printf("2.在某位置插入\n");
        printf("3.在某位置删除\n");
        printf("4.删除特定值\n");
        printf("5.输出\n");
        printf("输入1-5：");
        scanf("%d",&i);
        switch(i)
        {
        case 1:
            {
                L=create();
                break;
            }
        case 2:
            {
                printf("在哪里插入，插入啥:");
                scanf("%d %d",&i,&j);
                L=insert(L,i,j);
                break;
            }
        case 3:
            {
                printf("删除哪个位置:");
                scanf("%d",&i);
                L=deletepos(L,i);
                break;
            }
        case 4:
            {
                printf("删除特定值:");
                scanf("%d",&i);
                L=deleteelem(L,i);
                break;
            }
        case 5:
            {
                show(L);
                break;
            }
        }
    }