C language course set up library information management system (big homework)

One 、 Design function ( The article is for reference only )

Book information includes ： Login number 、 Title 、 The author's name 、 Classification number 、 Publisher 、 Publication date 、 Price etc. . Try to design a library information management system , It can provide the following functions ：
（1） The system works as a menu
（2） Book information input function ( Books and information are preserved in files )－－ Input
（3） Book information browsing function －－ Output
（4） Book information inquiry function －－ Algorithm
A query ： Search by title ; Search by author name
（5） Deletion and modification of book information ( optional )

Two 、 Function display

3、 ... and 、 Mind mapping

Four 、 Program source code

#include <stdio.h>/* Reference library functions */
#include <string.h>
#include <conio.h>
#include <stdlib.h>
#include <windows.h>


typedef struct book_info// Define the structure variable of the book information and declare the new type name 
{
    
  char AN[10];            /* Login number */
  char name[20];          /* Title */
  char author[20];       /* The author's name */
  char clc[10];          /* Classification of */
  char company[20];      /* Publisher */
  char date[20];         /* Publication date */
  char price[10];        /* Price */
  struct book_info*next;
}Booklist,*Pointer;

int num=0;// Definition of global variables 
Pointer Head=NULL;// The header pointer is empty 

FILE*fp;// Pointer to file 



               /* Declare functions */

int menu_select();/* Main menu function */
void Insert(Pointer*Head);/* Input function */
void Scan(Pointer Head);/* Show function */
void Search_name(Pointer Head);/* Find functions by book title */
void Search_author(Pointer Head);/* Find function by author name */
void Listbyname(Pointer*Head);/* Sort functions by book title */
void Delete(Pointer*Head);// Delete function 
void Update(Pointer Head);// Modify the function 
void Save();// Save the function as a text file 
void Read();// Read in text file function 
void Exit();// Exit function 



int main()// The main function 
{
    
  system("cls");/* Screen clearing before operation */
  for(;;)
 {
    
   switch(menu_select())
   {
    
    case 1:Insert(&Head);
           break;
    case 2:Scan(Head);
           break;
    case 3:Search_name(Head);
           break;
    case 4:Search_author(Head);
           break;
    case 5:Listbyname(&Head);
           break;
    case 6:Delete(&Head);
           break; 
    case 7:Update(Head);
           break;
    case 8:Save();
           break;
    case 9:Read();
           break;
    case 0:Exit();
    default:
    putchar('\a');
   }
 }
}



int menu_select()// Main menu function 
{
    
  int a;
  printf("\n\t\t\t Welcome to the library information management system \n\n\n\n\n\t\t***** Please press any key to enter the system menu !*****\n");
  getch();
  system("cls");
  printf("\t\t********************MENU*********************\n");// The main menu 
  printf("\t\t 1. Enter book information \n");
  printf("\t\t 2. Browse book information \n");
  printf("\t\t 3. Query book information by book title \n");
  printf("\t\t 4. Query book information by author name \n");
  printf("\t\t 5. Book information sorting \n");
  printf("\t\t 6. Delete book information \n");
  printf("\t\t 7. Modify book information \n");
  printf("\t\t 8. Book data storage \n");
  printf("\t\t 9. Open the book information file \n");
  printf("\t\t 0. sign out \n");
  printf("\t\t***********************************************\n");
  do
 {
    
  printf("\n\t Please select the service you need ：");
  scanf("%d",&a);
 }
 while(a<0||a>9);
 return a;
}


void Insert(Pointer*Head)// Enter the book information function 
{
    
 char AN[10];
 char c;
 Pointer p,q,r;
 printf("\n\t\t**************** Please enter book information ****************\n");/* Interactive input */
 printf("\n\t\t Please enter your login number :");
 scanf("%s",AN);
 p=q=*Head;// Check whether the login number is duplicate 
 while(p!=NULL)
 {
      
   if(strcmp(p->AN,AN)==0)
   {
    
    printf(" Already have the same login number ：");
	return;
   }
   else
   {
    
    q=p;p=p->next;
   }
 }
  r=(Pointer)malloc(sizeof(Booklist));
  r->next=NULL;
  if(r==NULL)
  {
    
    printf(" Failed to allocate space !");
	return;
  }
  if(q==NULL)
  *Head=r;
  else
  {
    
    q->next=r;
  }
   strcpy(r->AN,AN);
   printf("\n\t\t Enter the title of the book :");// Enter book information 
   scanf("%s",r->name);
   getchar();
   printf("\n\t\t Enter the author name :");
   scanf("%s",r->author);
   getchar();
   printf("\n\t\t Enter the classification number :");
   scanf("%s",r->clc); 
   getchar();
   printf("\n\t\t Enter the publishing unit :");
   scanf("%s",r->company);
   getchar();
   printf("\n\t\t Enter the publication date :");
   gets(r->date);
   printf("\n\t\t Enter the price :");
   scanf("%s",r->price);
   do
   {
     
      printf("\n\t\t Input succeeded !!!!");
      num++;
      printf(" Select whether to continue to enter (Y/N)?：");   /* Continuously input book information */
      getchar();
      scanf("%c",&c);
      if(c=='y'||c=='Y') 
	  Insert(Head);
      else
      {
    
        if(c=='n'||c=='N')
        return;
        else
        printf("\n\t\t Input error , Please re-enter !!!");
      }
   } 
     while(c!='y'&&c!='n'&&c!='Y'&&c!='N');
}


void Scan(Pointer Head)// Display book information function 
{
    
 Pointer p;
 p=Head; 
 if(p==NULL)
 printf(" Record is empty ");// Check whether there is book information 
 else
 {
    
   printf("\n\t share %d Bar record ",num);
   while(p!=NULL);
   {
    
     printf("\n\n\t\t Login number ：%-10s",p->AN);// Show book information 
     printf("\n\t\t Title ：%-20s",p->name);
     printf("\n\t\t The author's name ：%-20s",p->author);
     printf("\n\t\t Classification number ：%-10s",p->clc);
     printf("\n\t\t Publisher ：%-20s",p->company);
     printf("\n\t\t Publication date ：%-20s",p->date);
     printf("\n\t\t Price ：￥%-10s",p->price);
     p=p->next;
   }
    printf("\n\t\t Please press any key to return to the main menu ");
    return;
 }
}

void Search_name(Pointer Head)// Find functions by book title 
{
    
  int flag=0;// Mark the initial value of the variable 
  char name[10];
  Pointer p;
  printf ("\n Please enter the title of the book to be queried ：");
  scanf("%s",name);
  printf("\n\t\t************* Here is the information you are looking for ***************");
  p=Head;
  while(p!=NULL);
  {
    
    if(strcmp(p->name,name)==0)// Find books that match 
    {
    
     printf("\n\t Login number ：%-10s",p->AN);
     printf("\n\t Title ：%-20s",p->name);
     printf("\n\t The author's name ：%-20s",p->author);
     printf("\n\t Classification number ：%-10s",p->clc);
     printf("\n\t Publisher ：%-20s",p->company);
     printf("\n\t Publication date ：%-20s",p->date);
     printf("\n\t Price ：￥%-10s",p->price);
     flag=1;// Find the tag variable set to 1
     p=p->next;// The pointer goes to the next node 
    }
    else
    p=p->next;
  }
  if(flag==0)
  printf("\n\t\t There is no record of the same title ");
  printf("\n\t\t Please press any key to return to the main menu ");
  getchar();
}


void Search_author(Pointer Head)  // Find function by author name 
{
    
 int flag=0;
 char author[10];
 Pointer p;
 printf("\n Please enter the author name to query ：");
 scanf("%s",author);
 printf("\n\t\t************* Here is the information you are looking for ?***************");
 p=Head;
 while(p!=NULL);// Find books that match 
 {
    
  if(strcmp(p->author,author)==0)/* Find the book display information */
  {
    
   printf("\n\t Login number ：%-10s",p->AN);
   printf("\n\t Title ：%-20s",p->name);
   printf("\n\t The author's name ：%-20s",p->author);
   printf("\n\t Classification number ：%-10s",p->clc);
   printf("\n\t Publisher ：%-20s",p->company);
   printf("\n\t Publication date ：%-20s",p->date);
   printf("\n\t Price ：￥%-10s",p->price);
   flag=1;
   p=p->next;
  }
  else
  p=p->next;
 }
  if(flag==0)
  printf("\n\t\t There is no record of the same author name ");
  printf("\n\t\t Please press any key to return to the main menu ");
  getch();
}


void Listbyname(Pointer*Head)// Sort functions by book title ?
{
    
  Pointer p,q;
  int i,j;
  char t[10];
  char c;
  if(Head==NULL)
  {
    
    printf("\n\t\t No information ！\n");
    return;
  }
   if(num==0)// Check whether there is data to sort 
  {
      
   printf("\n\t\t The book information record is empty ！！ Please press any key to return to the main menu .");
   getchar();
   return;
  }
   p=q=*Head;
   for(i=0;i<num;i++)// Sort 
{
    
 for(j=i+1;j<num;j++)
 {
    
  q=p;
  p=p->next;// Make the pointer point to the next node 
  if(strcmp(q->name,p->name)>0)// Check both rows 
  {
                               //p The data corresponding to the pointer should be arranged in q After the pointer corresponds to the data ,p,q Data exchange 
   strcpy(t,p->AN);
   strcpy(p->AN,q->AN);
   strcpy(q->AN,t);
   strcpy(t,p->author);
   strcpy(p->author,q->author);
   strcpy(q->author,t);
   strcpy(t,p->clc);
   strcpy(p->clc,q->clc);
   strcpy(q->clc,t);
   strcpy(t,p->company);
   strcpy(p->company,q->company);
   strcpy(q->company,t);
   strcpy(t,p->date);
   strcpy(p->date,q->date);
   strcpy(q->date,t);
   strcpy(t,p->name);
   strcpy(p->name,q->name);
   strcpy(q->name,t);
   strcpy(t,p->price);
   strcpy(p->price,q->price);
   strcpy(q->price,t);
  }
 }
  q=*Head;p=*Head;
}
   
  do
  {
    
  printf("\n\t Sort complete , Whether or not shown (Y/N)：");   /* Ask whether to display the sorting results */
  getchar();
  scanf("%c",&c);
  if(c=='y'||c=='Y')
  Scan(*Head);  // Show sorting results 
  else
 {
    
    if(c=='n'||c=='N')
    return; // Back to main menu 
    else
    printf("\n\t\t Input error , Please re-enter !!!");// If there is an error, continue to ask 
 }
  }
   while(c!='y'&&c!='n'&&c!='Y'&&c!='N');
}


void Delete(Pointer*Head)/* Delete function */
{
    
 int flag=1;
 char AN[10];
 char c,z;
 Pointer p,q;
 printf("\n\t\t******************* Book deletion *******************\n");
 printf("\t Please enter the login number to delete the information of the book ：");
 scanf("%s",AN);
 p=q=*Head;/* Find books that match the criteria */
 while(p!=NULL&&flag);
 {
    
  if(strcmp(p->AN,AN)==0)/* Find the book */
  {
    
   printf("\t\n Login number ：%-10s",p->AN);// Display information about the book to be deleted 
   printf("\t\n Title ：%-20s",p->name);
   printf("\t\n The author's name ：%-20s",p->author);
   printf("\t\n Classification number ：%-10s",p->clc);
   printf("\t\n Publisher ：%-20s",p->company);
   printf("\t\n Publication date ：%-20s",p->date);
   printf("\t\n Price ：￥%-10s\n",p->price);
   printf(" Sure to delete ? Please enter if you are sure Y, Others will not be deleted ");// Ask if you want to delete 
   getchar();
   scanf("%c",&z);
   if(z=='Y'||z=='y')
   {
    
    if(p==*Head)
    {
    
	  *Head=p->next;free(p);
	}/* Delete book information */
    else
    {
    
	 q->next=p->next;
	 free(p);
	}
      flag=0;
   }
   else
   {
    
     printf(" The book information has not been deleted , Back to main menu .");
     return;
   }
 }
 else
 {
    
  q=p;p=p->next;
 }/* The pointer goes to the next node */
  printf("\t\t Delete successful ！！！\n");
}
  if(flag)
  printf("\t No data to delete !!!");
  do
  {
    
   printf(" Choose whether to continue deleting (Y/N)?：");  /* Delete book information continuously */
   getchar();
   scanf("%c",&c);
   if(c=='y'||c=='Y')
   Delete(Head); /* Continue to delete */
   else
  {
    
   if(c=='n'||c=='N')
   return;/* Return to the main menu without deleting */
   else
   printf("\n\t\t Input error , Please re-enter !!!");
  }
  }
   while(c!='y'&&c!='n'&&c!='Y'&&c!='N');
}

void Update(Pointer Head)/* Book information modification function */
{
    
  int flag=1;
  char AN[10];
  char c;
  Pointer p;
  printf("\n\t\t***************** Book information modification *****************\n");
  printf("\t Please enter the login number of the book to be modified ：");
  scanf("%s",AN);/* Find books that match the criteria */
  p=Head;
  while(p!=NULL&&flag); 
  {
    
   if(strcmp(p->AN,AN)==0)
   {
    
   printf("\n\t\t Please enter your login number :");/* Modify book information */
   scanf("%s",p->AN);
   printf("\n\t\t Enter the title of the book :");
   scanf("%s",p->name);
   getchar();
   printf("\n\t\t Enter the author name :");
   scanf("%s",p->author);
   getchar();
   printf("\n\t\t Enter the classification number :");
   scanf("%s",p->clc);
   getchar();
   printf("\n\t\t Enter the publishing unit :");
   scanf("%s",p->company);
   getchar();
   printf("\n\t\t Enter the publication date :");
   gets(p->date);
   printf("\n\t\t Enter the price :");
   scanf("%s",p->price);
   flag=0;
   printf(" Modification successful !!\n");
   }
   else
   p=p->next;/* The pointer goes to the next node */
 }
  if(flag)
  printf("\n\t\t There is no record of this book !!!");
  do
  {
    
   printf(" Select whether to continue to modify (Y/N)："); /* Continuously modify book information */
   getchar();
   scanf("%c",&c);
   if(c=='y'||c=='Y')
   Update(Head);/* Continue to modify */
   else
   {
    
    if(c=='n'||c=='N')
    return;// Don't modify , Go back to the menu 
    else
    printf("\n\t\t Input error , Please re-enter !!!");
   }
  }
    while(c!='y'&&c!='n'&&c!='Y'&&c!='N');// Continue to ask if the input is wrong 
}


void Save()     /* Functions saved as text files */
{
    
 Pointer p;
 p=Head;
 char file[20];  /* Used to store the file save path and file name */
 printf(" Please enter the file path and file name :");
 scanf("%s",file);
 if((fp=fopen(file,"w+"))==NULL)/* Determine whether the file can be opened */
{
    
 printf(" Can't open file !\n");
 return;
}
 while(p!=NULL);
 {
    
   fprintf(fp,"%s\t%s\t%s\t%s\t%s\t%s\t%s\n",p->AN,p->name,p->author,p->clc,p->company,p->date,p->price);// Write data to file 
   p=p->next;/* Move down one node */
 }
  fclose(fp);// Write completion , Close file 
  printf(" The file has been saved !\n");
  return;
}

void Read()/* Functions that read text files */
{
    
  Pointer p,q;
  int m=0;
  char file[20];
  printf(" Please enter the file path and file name :");
  scanf("%s",file);/* Enter the file path and name */
  if((fp=fopen(file,"r+"))==NULL)// Check if the file exists 
  {
    
   printf(" Can't open file !\n");
   return;
  }
  m=m+1;
  if(m==1)
  {
    
   p=(Pointer)malloc(sizeof(Booklist));/* Open up a new unit */
   Head=p;// take p To the header pointer Head
   fscanf(fp,"%s\t%s\t%s\t%s\t%s\t%s\t%s\t\n",&p->AN,&p->name,&p->author,&p->clc,&p->company,&p->date,&p->price);/* File read in */
   do
   {
    
   num=num+1;// Record the amount of information in books 
   if(num==1)// Distinguish between the beginning and the middle of the open list 
   Head->next=p;
   else
   q->next=p;
   q=p;
   p=(Pointer)malloc(sizeof(Booklist));/* Open up a new unit */
   fscanf(fp,"%s\t%s\t%s\t%s\t%s\t%s\t%s\t\n",&p->AN,&p->name,&p->author,&p->clc,&p->company,&p->date,&p->price);// Read in file data 
   }
    while(!feof(fp));// Check that the file is closed , If yes, stop reading , Otherwise, continue to read 
    q->next=p;
    p->next=NULL;// End of linked list processing 
    num=num+1;// The right amount of book information 
  }
   printf(" Write data successfully , You can go back and browse its information .");
   fclose(fp);/* End reading , Close file */
   return;
}


void Exit()/* Function to exit the program */
{
    
 char c;
 do
 {
    
  printf("\n\t\t Exiting ...... Whether to save to file (Y/N)?");/* Ask whether to save book information , To prevent loss */
  getchar();
  scanf("%c",&c);
  if(c=='y'||c=='Y')
  {
    
   Save();
   exit(0);
  }
  else
  {
    if(c=='n'||c=='N')
  {
    exit(0);}
  else
  printf("\n\t\t Input error , Please re-enter !!!");
  }
}
while(c!='y'&&c!='n'&&c!='Y'&&c!='N');// If there is an error, continue to ask 
}

You can pay attention to it, and it will be updated continuously in the future 0.0（ Thank you first ）