HANDLING RANDOM ACCESS FILE

SOURCE CODE:
#include<iostream.h>
#include<conio.h>
#include<fstream.h>
#include<iomanip.h>
class INVENTORY
{
 char name[10];
 int code;
 float cost;
 public:
    void getdata(void)
    {
     cout<<"Enter name: ";
     cin>>name;
     cout<<"Enter code: ";
     cin>>code;
     cout<<"Enter cost: ";
     cin>>cost;
   }
  void putdata(void)
  {
   cout<<setw(10)<<name<<setw(10)<<code<<setprecision(2)<<setw(10)<<cost<<endl;
  }
};
void main()
{
 clrscr();
 INVENTORY item;
 fstream inoutfile;
 inoutfile.open("STOCK.DAT",ios::ate|ios::in|ios::out|ios::binary);
 inoutfile.seekg(0,ios::beg);
 cout<<"CURRENT CONTENTS OF STOCK\n";
 while(inoutfile.read((char*)&item,sizeof item))
  {
   item.putdata();
  }
 inoutfile.clear();
 cout<<"\nADD AN ITEM\n";
 item.getdata();
 char ch;
 cin.get(ch);
 inoutfile.write((char *)&item,sizeof item);
 inoutfile.seekg(0);
 cout<<"CONTENTS OF APPENDED FILE\n";
 while(inoutfile.read((char *)&item,sizeof item))
  {
   item.putdata();
  }
 int last=inoutfile.tellg();
 int n=last/sizeof(item);
 cout<<"Number of objects = "<<n<<"\n";
 cout<<"Total bytes in the file = "<<last<<"\n";
 cout<<"Enter object number to be updated : ";
 int object;
 cin>>object;
 cin.get(ch);
 int location = (object-1)*sizeof(item);
 if(inoutfile.eof())
 inoutfile.clear();
 inoutfile.seekp(location);
 cout<<"Enter new values of the object\n";
 item.getdata();
 cin.get(ch);
 inoutfile.write((char *)&item,sizeof item)<<flush;
 inoutfile.seekg(0);
 cout<<"CONTENTS OF UPDATED FILE\n";
 while(inoutfile.read((char *)&item,sizeof item))
  {
   item.putdata();
  }
 inoutfile.close();
 getch();
}

OUTPUT:

CURRENT CONTENTS OF STOCK
AA    11    100
BB    22    200
CC    33    300
DD    44    400
XX    99    900

ADD AN ITEM
Enter name:YY
Enter code:10
Enter cost:101

CONTENTS OF APPENDED FILE
AA    11    100
BB    22    200
CC    33    300
DD    44    400
XX    99    900
YY    10    101

Number of objects = 6
Total bytes in the file = 96
Enter object number to be updated : 6
Enter new values of the object
Enter name:ZZ
Enter code:20
Enter cost:201

CONTENTS OF UPDATED FILE
AA    11    100
BB    22    200
CC    33    300
DD    44    400
XX    99    900
YY    10    101
ZZ    20    201
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