# include & ltstdio.h & gt
# include & ltmath.h & gt
# include & ltstring.h & gt
# include & ltstdlib.h & gt
Structural Books _ List
{
Char author [20]; /* Author's name */
char bookname[20]； /* Title */
char publisher[20]； /* Publisher */
char Pb time[ 15]； /* Date of publication */
char loginnum[ 10]； /* Login number */
Floating price; /* Price */
char classfy[ 10]； /* Classification number */
Struct books _ list * next/* pointer field of linked list */
};
struct Books _ list * Create _ Books _ Doc()； /* Create a new linked list */
void insert doc(struct books _ list * head)； /* Insert */
void delete doc(struct books _ list * head，int num)； /* Delete */
void Print _ Book _ Doc(struct books _ list * head)； /* Browse */
void search _ book(struct books _ list * head)； /* Query */
void info _ change(struct books _ list * head)； /* Modify */
void save(struct books _ list * head)； /* Save data to a file */
/* Create a new linked list header node */
struct Books _ list * Create _ Books _ Doc()
{
Structure books _ list * head
head =(struct books _ list *)malloc(size of(struct books _ list))； /* Allocate head node space */
head->； Next = NULL/* The pointer field of the head node is initialized and set to null */
Return head;
}
/* Save data to a file */
void save(struct books_list * head)
{
Structure books _ list * p；;
FILE * fp
P = head;
fp=fopen("data.txt "，" w+")； /* Create and open the data.txt file by writing */
fprintf(fp,"┏━━━┳━━━━━┳━━━━━┳━━━━━┳━━━━━━┳━━━┳━━━━┓\n”)； /* Output the table to a file */
Fprintf(fp,"┃ registration number ┃ title ┃ author ┃ publishing unit ┃ publishing time ┃ classification number ┃ price \ n);
fprintf(fp,"┣━━━╋━━━━━╋━━━━━╋━━━━━╋━━━━━━╋━━━╋━━━━┫\n”)；
/* The pointer moves from the head node to the tail node, and the book information is output in turn */
while(p->； Au Suivant! = empty)
{
p = p-& gt； Next;
fprintf(fp,"┃%-6.6s┃%- 10. 10s┃%- 10. 10s┃%- 10. 10s┃%- 12. 12s┃%-6.6s┃%.2f ┃\n",p->； loginnum，p-& gt； Title, p-> Author, P-> Publisher, P-> pbtime，p-& gt； classfy，p-& gt； Price);
}
fprintf(fp,"┗━━━┻━━━━━┻━━━━━┻━━━━━┻━━━━━━┻━━━┻━━━━┛\n”)；
fclose(FP)；
Printf ("Book data has been saved to data.txt file \ n");
}
/* Insert */
void insert doc(struct books _ list * head)
{
/* Define the first address p of the structure pointer variable S pointing to the opened new node as the intermediate variable */
struct books_list *s，* p；
Char flag =' Y/* defines the flag, which is convenient for users to select repeated input */
P = head;
/* Traverse to the tail node, p points to the tail node */
while(p->； Au Suivant! = empty)
{
p = p-& gt； Next;
}
/* Open a new space, store data and add it to the linked list */
while(flag=='Y'||flag=='y ')
{
s =(struct books _ list *)malloc(size of(struct books _ list))；
Printf ("\ nPlease enter the book login number:");
fflush(stdin)；
scanf("%s "，s-& gt； loginnum)；
Printf ("\ nPlease enter a title:");
fflush(stdin)；
scanf("%s "，s-& gt； Title);
Printf ("\ nPlease enter the name of the book author:");
fflush(stdin)；
scanf("%s "，s-& gt； Author);
Printf ("\ nPlease enter a book publisher:");
fflush(stdin)；
scanf("%s "，s-& gt； Publishers);
Printf ("\ nPlease enter the book publishing time:");
fflush(stdin)；
scanf("%s "，s-& gt； Pb time)；
Printf ("\ nPlease enter the book classification number:");
fflush(stdin)；
scanf("%s "，s-& gt； classfy)；
Printf ("\ nPlease enter the book price:");
fflush(stdin)；
scanf("%f "，& amps-& gt； Price);
printf(" \ n ")；
p->； next = s； /* Add the newly added node to the linked list */
p = s； /*p Point to the tail node and move back */
s-& gt； next = NULL
Printf ("━ ━ ━ added successfully! ━━━━");
Printf ("\ nContinue to add? (Y/N):)；
fflush(stdin)；
Scanf("%c ",& flag);
printf(" \ n ")；
if(flag=='N'||flag=='n ')
{ break}
else if(flag=='Y'||flag=='y ')
{Continue; }
}
Save (header); /* Save data to a file */
Return;
}
/* Query operation */
void search _ book(struct books _ list * head)
{
Structure books _ list * p；;
Charging temperature [20];
P = head;
if(head = = NULL | | head-& gt； Next==NULL) /* Determine whether the database is empty */
{
Printf ("━ ━ ━ Library is empty! ━━━\ n ")；
}
other
{
Printf ("Please enter the title of the book you are looking for:");
fflush(stdin)；
scanf("%s "，temp)；
/* The pointer moves from the head node to the tail node to find bibliographic information */
while(p->； Au Suivant! = empty)
{
p = p-& gt； Next;
if(strcmp(p-& gt； bookname，temp)==0)
{
Printf ("\ nFound a book! \ n ")；
printf(" \ n ")；
Printf ("login number: %s\t\n", p-> loginnum)；
Printf ("Title: %s\t\n "，p-& gt； Title);
Printf ("Author's name: %s\t\n", p-> Author);
Printf ("Publisher: %s\t\n "，p-& gt； Publishers);
Printf ("Release Date: %s\t\n", p-> Pb time)；
Printf ("classification number: %s\t\n", p-> classfy)；
Printf ("price: %.2f\t\n "，p-& gt； Price);
}
If (p->; next==NULL)
{
Printf ("\ nQuery complete! \ n ")；
}
}
}
Return;
}
/* Browse operation */
void Print _ Book _ Doc(struct books _ list * head)
{
Structure books _ list * p；;
if(head = = NULL | | head-& gt； Next==NULL) /* Determine whether the database is empty */
{
Printf ("\ n ━ ━ No book records! ━━━\ n \ n ")；
Return;
}
P = head;
printf("┏━━━┳━━━━━┳━━━━━┳━━━━━┳━━━━━━┳━━━┳━━━━┓\n”)；
Printf("┃ login number ┃ title ┃ author ┃ publishing unit ┃ publishing time ┃ classification number ┃ price ┃ n ");
printf("┣━━━╋━━━━━╋━━━━━╋━━━━━╋━━━━━━╋━━━╋━━━━┫\n”)；
/* The pointer moves from the head node to the tail node, and the book information is output in turn */
while(p->； Au Suivant! = empty)
{
p = p-& gt； Next;
printf("┃%-6.6s┃%- 10. 10s┃%- 10. 10s┃%- 10. 10s┃%- 12. 12s┃%-6.6s┃%.2f ┃\n",p->； loginnum，p-& gt； Title, p-> Author, P-> Publisher, P-> pbtime，p-& gt； classfy，p-& gt； Price); /* Circular output table */
}
printf("┗━━━┻━━━━━┻━━━━━┻━━━━━┻━━━━━━┻━━━┻━━━━┛\n”)；
printf(" \ n ")；
}
/* Modify operation */
void info _ change(struct books _ list * head)
{
Structure books _ list * p；;
int pan Duan = 0； /* This variable is used to judge whether the document directory is found */
Charging temperature [20];
P = head;
Printf ("Please enter the title of the book to be modified:");
scanf("%s "，temp)；
while(p->； Au Suivant! = empty)
{
p = p-& gt； Next;
if(strcmp(p-& gt； bookname，temp)==0)
{
Printf ("\ nPlease enter the book login card number:");
fflush(stdin)；
scanf("%s "，p-& gt； loginnum)；
Printf ("\ nPlease enter a title:");
fflush(stdin)；
scanf("%s "，p-& gt； Title);
Printf ("\ nPlease enter the name of the book author:");
fflush(stdin)；
scanf("%s "，p-& gt； Author);
Printf ("\ nPlease enter a book publisher:");
fflush(stdin)；
scanf("%s "，p-& gt； Publishers);
Printf ("\ nPlease enter the book publishing time:");
fflush(stdin)；
scanf("%s "，p-& gt； Pb time)；
Printf ("\ nPlease enter the book classification number:");
fflush(stdin)；
scanf("%s "，p-& gt； classfy)；
Printf ("\ nPlease enter the book price:");
fflush(stdin)；
scanf("%f "，& ampp->； Price);
printf(" \ n ")；
panduan = 1；
}
}
if(panduan==0)
{
Printf ("\ n ━ ━ No book records! ━━━\ n \ n ")；
}
Return;
}
/* Delete operation */
void delete doc(struct books _ list * head)
{
struct books_list *s，* p； /*s is an intermediate variable and p is a pointer */
Charging temperature [20];
Int panduan/* This variable is used to judge whether the document catalogue has been found */
panduan = 0；
P = s = head;
Printf("[ Please enter the title of the book you want to delete]:);
scanf("%s "，temp)；
/* Traverse to the tail node */
And (p! = empty)
{
if(strcmp(p-& gt； bookname，temp)==0)
{
Pan Duan++;
Break;
}
p = p-& gt； Next;
}
if(panduan== 1)
{
for(； s-& gt； Au Suivant! = p； )/* Find the previous node and delete the card number node */
{
s = s-& gt； Next;
}
s-& gt； next = p-& gt； Next; /* Assign the address of the latter node to the pointer field of the previous node */
Free (p);
Printf ("\ n ━ ━ deleted successfully! ━━━\ n ")；
}
Else /* No corresponding bibliography found */
{
Printf ("The bibliography you entered does not exist, please confirm and enter! \ n ")；
}
Return;
}
int main(void)
{
Structure books _ list * head
Char selection;
head = NULL
for(； ; )/* Realize repeated input and selection */
{
printf(“┏━┓━━━━━━━━━━━━━━━━━━━┏━┓\n”)；
Printf(“┃┃\n socat book management system ").
printf(“┃┗━━━━━━━━━━━━━━━━━━━┛┃\n”)；
Printf(" ┃ ●[ 1] book information entry ┃\ n ");
printf(“┃┃\n”)；
Printf(" ┃ ●[2] book information browsing ┃\ n ");
printf(“┃┃\n”)；
Printf(" ┃ ●[3] book information query ┃\ n ");
printf(“┃┃\n”)；
Printf(" ┃ ●[4] book information modification ┃\ n ");
printf(“┃┃\n”)；
Printf(" ┃ ●[5] Delete book information ┃\ n ");
printf(“┃┃\n”)；
Printf(" ┃ ●[6] Exit the system ┃\ n ");
printf(“┗━━━━━━━━━━━━━━━━━━━━━━━┛\n”)；
Printf ("Please select:");
fflush(stdin)；
Scanf("%c ",& select);
if(choice==' 1 ')
{
if(head==NULL)
{
head = Create _ Books _ Doc()；
}
insert doc(head)；
}
else if(choice=='2 ')
{
Print_Book_Doc (header);
}
else if(choice=='3 ')
{
Search_book (header);
}
else if(choice=='4 ')
{
Info_change (header);
}
else if(choice=='5 ')
{
delete doc(head)；
}
else if(choice=='6 ')
{
printf(" \ n ")；
Printf ("│ │ │ │ │ Thanks for using the library management system │ │ n");
Break;
}
other
{
Printf ("━ ━ ━ input error, please re-enter! ━━━━");
Break;
}
}
Returns 0;
}