#include<stdio.h>
#include<stdlib.h>

typedef struct node{
    int data;
    struct node * next;
}Node;
//链表初始化
void init_list();
//链表插入
void insert_link(int ,Node *,Node *);
//根据节点值查找位置
void query_index_by_data(Node *,Node *);
//根据位置查找节点值
void query_data_by_index(Node *,Node *);
//链表打印
void print_link(Node *,Node *);
//根据节点值删除节点
void delete_link(Node *,Node *);
//链表销毁
void destory_link(Node *,Node **);
//系统初始化
void init_system();
char is_continue[0];
int main(){
    Node *head,*p;
    p = head = (Node *)malloc(sizeof(Node));
    head->next = NULL;
    int choose_method;
    while(1){
        init_system();
        scanf("%d",&choose_method);
        switch(choose_method){
            case 1:
                insert_link(1,p,head);
                break;
            case 2:
                insert_link(2,p,head);
                break;
            case 3:
                insert_link(3,p,head);
                break;
            case 4:
                query_index_by_data(p,head);
                break;
            case 5:
                query_data_by_index(p,head);
                break;
            case 6:
                print_link(p,head);
                break;
            case 7:
                delete_link(p,head);
                break;
            case 8:
                destory_link(p,&head);
                break;
            case 9://退出
                exit(0);
                break;
            default:
                printf("您是不是按错了\n");
                break;
        }
    }
}
void init_system(){
    printf("请选择操作\n");
    printf("1:从首部插入节点\n");
    printf("2:从尾部插入节点\n");
    printf("3:从指定位置追加\n");
    printf("4:根据值查找节点位置\n");
    printf("5:根据位置查找节点值\n");
    printf("6:输出节点\n");
    printf("7:删除节点\n");
    printf("8:清空链表\n");
    printf("9:退出\n");
}

void insert_link(int type,Node * list,Node * head){
    int data,index;
    while(1){
        int num = 0;
        printf("输入您想输入的数据\n");
        scanf("%d",&data);
        Node * new_node = (Node *)malloc(sizeof(Node));
        new_node->data = data;
        Node * p = head;
        switch(type){
            case 1://从首部插入数据
                new_node->next = head->next;
                head->next = new_node;
                break;
            case 2://从尾部插入数据
                new_node->next = list->next;
                list->next = new_node;
                list=list->next;
                break;
            case 3:
                printf("请输入您准备插入的位置\n");
                scanf("%d",&index);
                while(num<index&&p->next!=NULL){
                    p = p->next;
                    num++;
                }
                new_node->next = p->next;
                p->next = new_node;
                break;
        }
        printf("是否继续插入，输入Y/N\n");
        scanf("%s",is_continue);
        getchar();//清楚缓存区的符合
        if(strcmp(is_continue,"N")==0){
            break;
        }
    }
}

void query_index_by_data(Node * link,Node * head){
    int data;
    while(1){
        int num=0,flag=-1;
        printf("输入您想要查找的值\n");
        scanf("%d",&data);
        Node * p = link;
        while(p){
            if(p->data==data){
                flag = 1;
                break;
            }
            p = p->next;
            num++;
        }
        if(flag==1){
            printf("此值对应的位置是%d\n",num);
        }else{
            printf("此链表无对应的值\n");
        }
        printf("是否继续查找，输入Y/N\n");
        scanf("%s",is_continue);
        getchar();//清楚缓存区的符合
        if(strcmp(is_continue,"N")==0){
            break;
        }
    }
}

void query_data_by_index(Node * link,Node * head){
    int index;
    while(1){
        int num=0;
        printf("输入您想要查找的位置\n");
        scanf("%d",&index);
        Node * p = link;
        while(p&&num<index){
            p=p->next;
            num++;
        }
        printf("此位置对应的值是%d\n",p->data);
        printf("是否继续查找，输入Y/N\n");
        scanf("%s",is_continue);
        getchar();//清楚缓存区的符合
        if(strcmp(is_continue,"N")==0){
            break;
        }
    }
}

void print_link(Node * link,Node * head){
    Node * p = head->next;
    printf("链表数据:\n");
    while(p->next!=NULL){
        printf("%d ",p->data);
        p=p->next;
    }
    printf("%d\n",p->data);
}

void delete_link(Node * link,Node * head){
    int data;
    while(1){
        int flag=-1;
        Node * p,* q;
        printf("输入需要删除的节点值\n");
        scanf("%d",&data);
        p = head->next;
        q = head;
        while(p){
            if(p->data==data){
                q->next = p->next;
                flag = 1;
                break;
            }
            p = p->next;
            q = q->next;
        }
        if(flag==1){
            free(p);
            printf("节点删除成功\n");
        }else{
            printf("此链表找不到这个值\n");
        }
        printf("是否继续删除，输入Y/N\n");
        scanf("%s",is_continue);
        getchar();//清楚缓存区的符合
        if(strcmp(is_continue,"N")==0){
            break;
        }
        
    }
}

void destory_link(Node * link,Node ** head){
    Node * p = *head;
    Node * temp;
    while(p){
        temp = p->next;
        free(p);
        p = temp;
    }
    printf("已经清空链表\n");
}