How To Perform Write And Read Operation From A File In File Handling In C++

#include<iostream.h>

#include<conio.h>

#include<fstream.h>

struct stu

{

   int roll;char name[20];

 void getstu()

 {

  cout<<"\n\t Enter Roll and Name:\n";

  cout<<"Roll: ";cin>>roll;

  cout<<"\nName: ";cin>>name;

 }

 void putstu()

 {

  cout<<"\n\t Roll: "<<roll;

  cout<<"\n\t Name: "<<name;

 }

}s,s1;

void main()

{

 clrscr();

 ofstream f1;

 {

 s.getstu();

 f1.open("s.dat",ios::binary||ios::app);

 f1.write((char *)&s,sizeof(s));

 f1.close();

 }

 ifstream f2;

 {

 f2.open("s.dat",ios::binary);

 f2.read((char *)&s1,sizeof(s1));

 s1.putstu();

 }

}