A music shop sells CDs, DVDs, magazines and books. It is in need of a stock management system to maintain stock records with a text (command line) menu with options to allow the user to perform the following functionality: • sell items • restock items (increase stock quantity) • add new items • update stock quantity (correct stock levels) • view a report of sales It should also be possible to load and save the stock data to/from a file.

Answer:

/*------------------------------headers files---------------------------------------------*/
#include<iostream>
#include<conio.h>
#include<fstream>
#include<iomanip>
using namespace std;

#define file "stock.txt" // Constant define file name as file
fstream f;

/*----------------------------class defination -------------------------------------------*/
class Stock{
private:                                            //private member                                      
int book_qty;
   int magine_qty;
   int dvd_qty;
   int cd_qty;
  
public:                                           //public members  
   Stock()                //constructor
   {
   this->book_qty=0;
   this->magine_qty=0;
   this->cd_qty=0;
   this->dvd_qty=0;  
   }                                                
   void sell_item();                               //member functions   
   void restock();
   void add_new();
   void update();
   void show();
   void write_file();
   int read_file();
   void get();
   void report();
}st;                                               //global class object

int menu()                                                   //menu function
{
   int x=0;
cout<<"\n\n\t\t\t=========================Welcome to Stock Management System portal============================\n____________________________________________________________________________________________________________________\n\n";
   cout<<"\n Please choose what you want\n";
   cout<<"\t1. Sell item\n";
   cout<<"\t2. Restock\n";
   cout<<"\t3. Add new item\n";
cout<<"\t4. update stock\n";
   cout<<"\t5. report\n";
   cout<<"\t6. exit\n";
   cout<<"\n\n\t-->> Enter your choice only number..\n\t--> ";
   cin>>x;
   return x;
}

/*---------------------------------Main Function--------------------------*/
int main()
{
   system("color A");
do{
system("cls");  
int c=menu();
switch(c)
    {
       case 1:
st.sell_item();
       break;
   case 2:
       st.restock();
       break;
   case 3:
       {
       system("cls");
           int x=0;
       cout<<"\nEnter 1 for proceed **All data deleted and new one updated**\n\n ";
       cin>>x;
           if(x==1)
            st.add_new();
            else
            cout<<"\nplease wait and press enter";
              system("pause");
    }break;
    case 4:
       st.update();
       break;
   case 5:
       st.report();
       break;
    case 6:
        system("cls");
       cout<<setw(55)<<"Thank you for using our portal\n\n "<<setw(55);
       system("pause");
exit(0);
       break;
default:
            cout<<" \n\n\twrong choice\n\tplease press enter...\n\t ";
            getch();
            break;
}
}while(1);
getch();
  
}

/*------------------------class methods defination-------------------------------*/

void Stock::add_new(){
  
   system("cls");
st.get();
st.write_file();
cout<<"\n\n\t\t--------- Data Added successfully--------\n";  
getch();
  
  
  
  
}
int Stock::read_file()
{   
   f.close();
   f.open(file);
   f.read((char*)this,sizeof(Stock));
   if(f.good())
       return 1;
   else
       return 0;
}

void Stock::write_file()
{
f.close();
   f.open(file,ios::out);
   f.write((char*)this,sizeof(Stock));
}

void Stock::get(){
cout<<"\n-------------- Please provide given data -----------\n";
   cout<<"Enter the Books Quantity..\t ";
   cin>>this->book_qty;
   cout<<"Enter the DVDs Quantity..\t ";
   cin>>this->dvd_qty;
   cout<<"Enter the CDs Quantity..\t ";
   cin>>this->cd_qty;
   cout<<"Enter the Magines Quantity..\t ";  
   cin>>this->magine_qty;
}

void Stock::restock(){
   Stock ss,sa;
   system("cls");
   cout<<"\n\t--------- Please Enter Adding Values of Each ------------\n ";
   st.get();
   cout<<"\n\n\n --------before restock stacks -------\n\n";
sa.read_file();
sa.show();
   if(ss.read_file())
   {
       ss.book_qty=ss.book_qty+st.book_qty;
       ss.magine_qty=ss.magine_qty+st.magine_qty;
       ss.dvd_qty=ss.dvd_qty+st.dvd_qty;
       ss.cd_qty=ss.cd_qty+st.cd_qty;
       ss.write_file();
       cout<<"\n\n\n\n\n---------+++++++ item sell updated in stock ++++++---------\n\n";
       }
   else
       cout<<"\n data retreving error..... \n";
   cout<<"\n\n\n------------- after restock stacks updated----------------\n";
st.read_file();
st.show();
getch();
  
}
void Stock::sell_item(){
   Stock ss,sa;
   system("cls");
   cout<<"\n\t--------- Please Enter Selling Rate of Each ------------\n ";
   st.get();
   cout<<"\n\n\n --------before selling stacks -------\n\n";
sa.read_file();
sa.show();
   if(ss.read_file())
   {
       ss.book_qty=ss.book_qty-st.book_qty;
       ss.magine_qty=ss.magine_qty-st.magine_qty;
       ss.dvd_qty=ss.dvd_qty-st.dvd_qty;
       ss.cd_qty=ss.cd_qty-st.cd_qty;
       ss.write_file();
       cout<<"\n\n\n\n\n---------+++++++ item sell updated in stock ++++++---------\n\n";
       }
   else
       cout<<"\n data retreving error..... \n";
   cout<<"\n\n\n------------- after selling stacks updated----------------\n";
st.read_file();
st.show();
getch();
  
}
void Stock::update(){

int ch=0,a=0;
  
do{
   system("cls");
   cout<<"\n\n\n\t------------- before stock updated----------------\n";
st.read_file();
st.show();
int x,q;
   Stock ss;
   cout<<"\n\n\n\t--------- Please Enter Updating Values ------------\n ";
   cout<<"\n\nEnter what you want to update\n";
   cout<<"\n1.Books\t2.DVDs\t3.CDs\t4.Magine\t5.proceed further..\n";
   cin>>x;

   switch(x)
       {
           case 1:
               cout<<"\nenter the updating books quantity...\t";
               cin>>q;
               ss.cd_qty=st.cd_qty;
               ss.book_qty=q;
               ss.dvd_qty=st.dvd_qty;
               ss.magine_qty=st.magine_qty;
           break;
           case 2:
               cout<<"\nenter the updating DVDs quantity...\t";
               cin>>q;
               ss.cd_qty=st.cd_qty;
               ss.book_qty=st.book_qty;
               ss.magine_qty=st.magine_qty;
               ss.dvd_qty=q;
               break;
           case 3:
               cout<<"\nenter the updating CDs quantity...\t";
               cin>>q;
               ss.book_qty=st.book_qty;
               ss.dvd_qty=st.dvd_qty;
               ss.magine_qty=st.magine_qty;
               ss.cd_qty=q;
               break;
           case 4:
          cout<<"\nenter the updating magine quantity...\t";
               cin>>q;
               ss.cd_qty=st.cd_qty;
               ss.book_qty=st.book_qty;
               ss.dvd_qty=st.dvd_qty;
               ss.magine_qty=q;
               break;
           default:
           a=1;
               cout<<"\nenter valid choice..\t ";
               break;
       }
if(a != 1)
   {
    ss.write_file();
   cout<<"\n updated ";
   cout<<"\n\n\n------------- After stocks updated ----------------\n";
st.read_file();
st.show();
}
cout<<"\n\ndo you want to update another one press 1 or another for exit \t";
cin>>ch;
}while(ch==1);
getch();

}
void Stock::show(){
cout<<"\n\n Numbers of Book : \t "<<this->book_qty;
cout<<"\n\n Numbers of DVDs : \t "<<this->dvd_qty;
cout<<"\n\n Numbers of CDs : \t "<<this->cd_qty;
cout<<"\n\n Numbers of Magines : \t "<<this->magine_qty;
}

void Stock::report()
{
system("cls");
cout<<"\n\n\t----------------- Stock report --------------------\n";
    if(st.read_file())
                  st.show();
   else
   cout<<"please Add some data first.... ";
  
getch();  
}

OUTPUT:-

PFA