Program is to create a file student.dat:

Program is to create a file student.dat which contains all name, roll_no,marks(5 sub) and percentage

  class student

   {

   private:

    char name[20];

    int roll;

    int marks[5];

    int total;

    float perc;

   public:

    student()

     {

     total=0;

     }

     void input();

     void output();

     };

 void student::input()

  {

  clrscr();

  cout<<" enter your name ";

  gets(name);

  cout<<" enter your roll no. ";

  cin>>roll;

  cout<<" enter the marks of five subjects "<<"\n";

  for (int i=0;i<5;i++)

    {

    cout<<" enter marks";

    cin>>marks[i];

    total=total + marks[i];

    }

   }

 void student::output()

   {

   clrscr();

   perc=total/5;

    if (perc>=60)

      {

     cout<<" the name is "<

     cout<<" the total marks obtained out of (500) "<

     cout<<" the percentage "<

     }

    else

     cout<<" the percten tage is less then 60 ";

   }

  void main()

    {

    clrscr();

   student info;

   fstream file;

   file.open("student.dat",ios::in|ios::out);

   int n;

   cout<<" enter the number for which u want to enter data";

   cin>>n;

   for(int i=1;i<=n;i++)

     {

     info.input();

     file.write((char *)& info,sizeof(info));

     }

     file.close();

     file.open("student.dat",ios::in);

     while(file)

      {

    file.write((char *)& info,sizeof(info));

    info.output();

    }

   file.close();

   }