transaksi pembayaran SPP

#include "fstream.h"
#include "iomanip.h"

class INVENTORY{
char nama[50];
int NPM;
float cost;
public:
void getdata(void) {
cout<<"Enter nama: ";cin>>nama;
cout<<"Enter NPM: ";cin>>NPM;
cout<<"Enter cost: ";cin>>cost;
}
void putdata(void) {
cout< }
}; //End of class definition

void main()
{
INVENTORY item;

fstream inoutfile; //input/output stream
inoutfile.open("STOCK.DAT",ios ::ate |ios ::in| ios::out | ios::binary);
inoutfile.seekg(0,ios::beg); // go to start

{
cout << "\n####<<< PEMBAYARAN SPP >>>####\n";
cout << "\nData Mahasiswa\n\n";
item.getdata();
char ch;
cin.get(ch);
inoutfile.write((char*)&item,sizeof item);
cout << "\n\nTerima kasih telah melakukan pembayaran SPP 1 tahun\n\n";
}

};