c - 未执行排序

Question

这个程序是一个通过软件工作的图书馆。问题是当我按价格对书籍进行排序并打印它们时，它们永远不会被排序!

#include<stdio.h>
#include<conio.h>
#include<stdlib.h>
static int count;
struct book
{
    int bookid;
    char name[30];
    char author[30];
    float price;
};
struct book b[40];
void add(void);
void del(void);
void sort(void);
void price(void);
void print(void);
void main(void)
{
    char choice;
    while(1)
    {
        clrscr();
        printf("Enter a choice:\n 1.Add a book.\n 2.Delete a book.\n 3.Sort books by price.\n 4.To print all books details.\n 5.To print the names of the books whose price is less than 1000.\n 6.Exit\n");
        choice=getche();//doing by getch() as getche makes the program rough as it is printed
        switch(choice)
        {
            case'1':add();break;
            case'2':del();break;
            case'3':sort();break;
            case'4':print();break;
            case'5':price();break;
            case'6':exit(0);
            default:printf("Enter a valid choice.");break;
        }
    }/*switch ends*/
}
void add(void)
{
    int i;
    char ch[30];
    clrscr();
    for(i=count;i<40;i++)
    {
    printf("Enter books name:\n");
    gets(b[i].name);
    printf("Enter author's name\n");
    gets(b[i].author);
    printf("Enter price:\n");
    gets(ch);
    b[i].price=atoi(ch);
    b[i].bookid=count;
    break;
    } /* for ends*/
count++;
printf("Dear User,the book has succesfully been added.The book id is %d",b[i].bookid);


getch();
}
void print(void)
{
    int i;
    clrscr();
    for(i=0;i<count;i++)
    {
        printf("Bookid=%d,Name=%s,Author=%s,Price=%f\n",b[i].bookid,b[i].name,b[i].author,b[i].price);

    }
getch();
}

void del(void)
{
    int i,j;
    char ch[10];
    clrscr();
    printf("Enter book id:");
    gets(ch); // how do i put it into the structure as i dont know that which structure it belongs to
    for(i=0;i<count;i++)  //searching
    {
    if(b[i].bookid==atoi(ch))
        {
            for(j=i;j<count;j++)
            {

                b[j]=b[j+1];
            }//for j ends
        }  //if ends
    } /* for of i ends */
    count--;
    //  sort();
getch();
}
//void del(void)
//{

    //  int i;
    //  char ch[10];
     // clrscr();
    //printf("Enter book id:");
       //   gets(ch);
      //    for(i=0;i<40;i++)
      //    {
     //     b[i]=b[i+1];
    //
   //   }
    //  count--;
  //    printf("Dear user,delete succesful");
//getch();
//}
void sort(void)
{
    int in,out;
    struct book temp;
    for(out=0;out<count-1;out++)
    {
        for(in=out+1;out<count;out++)
        {
            if(b[out].price>b[in].price)
            {
                temp=b[out]
                b[out]=b[in];
                b[out]=temp;
            }
        }/*for out ends*/
    }//for in ends
    printf("Dear user,the books are sorted by price.\n");

getch();
}

void price(void)
{
    int i;
    clrscr();
    for(i=0;i<count;i++)
    {
        if(b[i].price<1000)
        {
        printf("%d.%s\n",i+1,b[i].name);
        }
    }
getch();

Answer 1

void sort(void)
{
    int in,out;
    struct book temp;
    for(out=0;out<count-1;out++)
    {
        //**(in=out+1;out<count;out++)**//look here please
        for(in=out+1;in<count;in++)
        {
            if(b[out].price>b[in].price)
            {
                temp=b[out]
                b[out]=b[in];
                b[in]=temp;//**b[out]=temp;**//look here plz
            }
        }/*for out ends*/
    }//for in ends
    printf("Dear user,the books are sorted by price.\n");

getch();
}