Create a class for inventory of books containing author, title, price, and publisher and stock as data members. Book can be sold, if stock is available, otherwise purchase will be made. Write necessary member functions for the following: 1. To accept details from user 2. To sale a book. (Sale contains book details & number of copies to be sold.) 3. To Purchase a book. (Purchase contains book details & number of copies to be purchased) (Use new operator to allocate memory).

#include<iostream.h>
#include<conio.h>
#include<stdlib.h>
int n;
class Inventory
{
char author[20],publisher[20],title[20];
int book_no,price,stock;
public:
void accept();
friend void sale(Inventory *,int,int);
friend void purchase(Inventory *,int,int)
void display();
};
void Inventory :: accept()
{
cout<<"\n Book Number    : ";cin>>book_no;
cout<<"\n Book Author    : ";cin>>author;
cout<<"\n Book Title     : ";cin>>title;
cout<<"\n Book Price     : ";cin>>price;
cout<<"\n Book Publisher : ";cin>>publisher;
cout<<"\n Stock of Book  : ";cin>>stock;
}
void Inventory :: display()
{
cout<<"\n\n Book Number    : "<<book_no;
cout<<"\n Book Author    : "<<author;
cout<<"\n Book Title     : "<<title;
cout<<"\n Book Price     : "<<price;
cout<<"\n Book Publisher : "<<publisher;
cout<<"\n Stock of Book  : "<<stock;
}
void sale(Inventory *I,int b_no,int Qty)
{
int f=0,f1=0;
for(int i=0;i<n;i++)
if(I[i].book_no==b_no)
{
f1=1;
if(I[i].stock>=Qty)
{
I[i].stock=I[i].stock-Qty;
I[i].display();
f=1;
}
}
if(f1==0)
{
cout<<"\n\nBook is not available check book number";
}
else
if(f==0)
cout<<"\n\nStock is not available please purchase book";
}
void purchase(Inventory *I,int b_no,int Qty)
{
int f=0;
for(int i=0;i<n;i++)
if(I[i].book_no==b_no)
{
I[i].stock=I[i].stock+Qty;
cout<<"\n\nStock is updated";
I[i].display();
f=1;
}
if(f==0)
cout<<"\n\nBook is not present check book number";

}


int main()
{
Inventory I[20];
clrscr();
int ch,b_no,Qty;
cout<<"\n\nEnter how many books detail you want to enter : ";
cin>>n;
do
{
cout<<"\n Main menu ";
cout<<"\n 1.Accept book details ";
cout<<"\n 2.Display book details ";
cout<<"\n 3.Sale book";
cout<<"\n 4.Purchase book ";
cout<<"\n 5.Exit ";
cout<<"\n Enter your choice : ";
cin>>ch;
switch(ch)
{
case 1: for(int i=0;i<n;i++)
I[i].accept();
break;
case 2: for(i=0;i<n;i++)
I[i].display();
break;
case 3: cout<<"\n\nEnter book number which you want to sale : ";
cin>>b_no;
cout<<"\n\nEnter book quantity :";
cin>>Qty;
sale(I,b_no,Qty);
break;
case 4:
cout<<"\n\nEnter book number which you want to purchase : ";
cin>>b_no;
cout<<"\nEnter book quantity :";
cin>>Qty;
purchase(I,b_no,Qty);
break;
case 5: exit(0);
}
}
while(ch!=5);
getch();
return(0);
}