图书馆管理系统之链表
输入那块应该有很大问题，请各路英雄指点迷津#include<stdio.h>
#include<stdlib.h>
#include<string.h>
struct books{
char booknum[20]; //书号
char bookname[20]; //书名
char authorname[20]; //作者
char cbs[20]; //出版社
char price[5]; //价格
struct books *next;
struct books *prior;
};
struct books *head; //头结点
struct books *last; //尾结点
int menu(void); //菜单选项
void inputs(char *prompt,char *s,int count);//输入格式
void enter(void); //信息输入
void dls_store(struct books *i,struct books **head,struct books **last);//按书号大小建立链表
struct books *find(char *bn); //按书名检索
void search(void); //按书名查找
void modify(void); //修改信息
void display(struct books *p); //显示格式
void list(void);
void del(struct books **head,struct books **last); //删除信息
void save(void); //以文件形式保存信息
void load(void); //从文件中载入信息
void inputs(char *prompt,char *s,int count)
{
char p[255];
do{
printf(prompt);
gets(p);
if(strlen(p) > count) //限定输入字符长度
{
printf("\nToo long\n");
}
}while(strlen(p) > count);
strcpy(s,p);
}
void enter(void) //输入信息
{
system("cls");//清屏
struct books *p;
p=(struct books *)malloc(sizeof(struct books));
char ch;
inputs("请输入书的编号:",p->booknum,20);
inputs("请输入书名:",p->bookname,20);
inputs("请输作者名:",p->authorname,20);
inputs("请输入出版社:",p->cbs,20);
inputs("请输入图书价格:",p->price,5);
printf("\n");
dls_store(p,&head,&last);
free(p);
}
void dls_store(struct books *i,struct books **head,struct books **last) //按书号顺序插入表中
{
struct books *p,*old;
if((*last) == NULL)
{
i->prior = NULL;
i->next = NULL;
(*head) = i;
(*last) = i;
return;
}
p = (struct books *)malloc(sizeof(struct books));
p = (*head);
old = NULL;
while(p!=NULL)
{
if(strcmp(p->booknum,i->booknum) < 0)
{
old = p;
p = p->next;
}
else
{
if(p->prior)
{
p->prior->next = i;
i->next = p;
i->prior = p->prior;
p->prior = i;
return;
}
i->next = p; //放表头
i->prior = NULL;
p->prior = i;
*head = i;
return;
}
}//end while
old->next = i;
i->next = NULL;
p->prior = i;
*last = i;
free(p);
}
struct books *find(char *bn) //按书名搜索关键字
{
struct books *p;
p = head;
while(p!=NULL)
{
if(strcmp(bn,p->bookname) == 0)
{
return p;
}
p = p->next;
}
return NULL;
}
void search(void)
{
char name[20];
struct books *p;
printf("请输入你要查询的书名:");
gets(name);
p = find(name);
if(p == NULL) printf("没有找到你查询的信息.\n");
else display(p);
}
void modify(void) //根据书名查找并修改信息
{
char name[20];
struct books *p;
printf("请输入你要查询的书名:");
gets(name);
p = find(name);
if(p == NULL) printf("没有找到你查询的信息.\n");
else
{
inputs("请输入书的编号:",p->booknum,20);
inputs("请输入书名:",p->bookname,20);
inputs("请输作者名:",p->authorname,20);
inputs("请输入出版社:",p->cbs,20);
inputs("请输入图书价格:",p->price,5);
printf("\n");
}
}
void display(struct books *p)
{
printf("%s\t",p->booknum); //书号
printf("%s\t",p->bookname); //书名
printf("%s\t",p->authorname); //作者
printf("%s\t",p->cbs); //出版社
printf("%s\t",p->price);
printf("\n");
}
void list(void)
{
system("cls");
struct books *p;
p = head;
printf("书号\t书名\t作者\t出版社\t价格\n");
while(p != NULL)
{
display(p);
p = p->next;
}
printf("\n");
}
void del(struct books **head,struct books **last)
{
struct books *i;
char s[50];
inputs("输入书名:",s,20);
i = find(s);
if(i)
{
if(*head == i)
{
*head = i->next;
if(*head) (*head)->prior = NULL;
else *last = NULL;
}
else
{
i->prior->next = i->next;
if(i != *last)
{
i->next->prior = i->prior;
}
else
{
*last = i->prior;
}
}
free(i);
}//end if(i)
}
void save(void)
{
struct books *p;
FILE *fp;
if((fp=fopen("books","wb")) == NULL)
{
printf("open file error.\n");
exit(1);
}
p = head;
while(p!=NULL)
{
fwrite(p,sizeof(struct books),1,fp);
p = p->next;
}
fclose(fp);
}
void load(void)
{
struct books *p;
FILE *fp;
fp=fopen("books","rb");
if(fp == NULL)
{
printf("open file error.\n");
exit(1);
}
while(head)
{
p = head->next;
free(p);
head = p;
}
head = last = NULL;
printf("\n 载入信息 \n");
while(!feof(fp))
{
p = (struct books *)malloc(sizeof(struct books));
if(1 != fread(p,sizeof(struct books),1,fp)) break;
dls_store(p,&head,&last);
}
fclose(fp);
}
int menu(void)
{
char s[20];
int c;
system("cls");
printf("\t\t*****************图书信息管理系统*****************\n");
printf("\t\t*\t\t|1.图书信息输入 *\n");
printf("\t\t*\t\t|2.图书信息浏览 *\n");
printf("\t\t*\t\t|3.图书信息查询 *\n");
printf("\t\t*\t\t|4.图书信息修改 *\n");
printf("\t\t*\t\t|5.图书信息删除 *\n");
printf("\t\t*\t\t|6.存储图书信息 *\n");
printf("\t\t*\t\t|7.载入图书信息 *\n");
printf("\t\t*\t\t|8.退出系统 *\n");
printf("\t\t*****************图书信息管理系统*****************\n\n\n");
printf("\t\t请输入以上序号进行选择:\n");
do{
gets(s);
c = atoi(s);
}while(c<0||c>8);
return c;
}
int main(void)
{
head = last = NULL;
while(1)
{
switch(menu())
{
case 1:enter();system("pause");//录入
break;
case 2:list();system("pause");//浏览
break;
case 3:search();system("pause");
break;
case 4:modify();system("pause");
break;
case 5:del(&head,&last);system("pause");
break;
case 6:save();system("pause");
break;
case 7:load();system("pause");
break;
case 8:exit(0);
}//end switch
}//end while
return 0;
}
