int newbook(BOOK *lastnode,int *n){        //lastnode is the lastnode of booklist , n is the number of books
    BOOK *newnode;

    /*  if expend the struct book , add sth here  */

    newnode=(BOOK *)malloc(sizeof(BOOK));
    if(newnode==NULL)return 0;
    *n=*n+1;
    newnode->id=*n;
    newnode->state=1;
    newnode->next=NULL;
    lastnode->next=newnode;
    lastnode=newnode;                    //replace the lastnode;
    return 1;
}                       //in main(),test newbook() and decide append lastnode to book.txt or not

int deletebook(BOOK *booklist,int id){
    BOOK *book=booklist;
    while(book){
        if(book->id==id){
            book->state=-1;
            return 1;}
        book=book->next;
    }
    return 0;
}    /*another solution is "blacklist" ,then when you init ,just delete that node*/

int newlicense(LICENSE *lastnode , int *n){            //see newbook()
    LICENSE *newnode;
    newnode=(LICENSE *)malloc(sizeof(LICENSE));
    if(newnode==NULL)return 0;
    *n=*n+1;
    newnode->id=*n;
    newnode->holding=0;
    newnode->next=NULL;
    lastnode->next=newnode;
    lastnode=newnode;
    return 1;
}
int deletelicense(LICENSE *llist,int id){        //see deletebook()
    /* infact we will never delete ,so there is no llist->state ....lol.... */
    return 1;
}

int newborrow(BRECORD *lastnode){
    int bookid,licenseid;
    BRECORD *newnode;
    printf("INPUT LICENSE ID & BOOK ID:")
    scanf("%d %d",&licenseid,&bookid);

    /*if you decide to check the record ,do it ,then you need two para:BOOK *booklist and LICENSE *list;*/
    /* but in fact ,we only borrow when we realy get the book */
    /* a machine do it better,so do you need a confirm? */

    newnode=(BRECORD *)malloc(sizeof(BRECORD));
    if(newnode==NULL)return 0;
    newnode->bookid=bookid;
    newnode->licenseid=licenseid;
    newnode->btime=time();
    newnode->next=NULL;
    lastnode->next=newnode;
    lastnode=newnode;
    return 1;   
}                            /* then ,test and append */
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I think I need a new struct of BRECORD and RRECORD;for the easier operation on newborrow and newreturn;

是用C语言么  只要程序 还是要系统啊

我们大一的时候就是这个程序  大二的时候就让我们做成系统实现