reading data from a file into an array of a class - c++

Question

//Student file
#include <iostream>
#include <fstream>
#include <string>
#include <iomanip>
using namespace std;
#include "student.h"
#define cap 100
void main()
{ string s;
class student student[cap],l;
int i;
fstream f;
i=0;
cout << "Enter the file name: "; //Display to enter the file name
cin >>s;
f.open(s.data(),ios::in);
if(!f.is_open())
cout << "could not open file";
while(i<cap && !f.eof())
{ cout << "good";
student[i].get(f);
//Display if okay
if(f.good())
{
i++;
student[i].put(cout);
cout << i;
}
}
f.close();
}
class student
{
public:
student(); //Constructor without parameters
student(int,string,string,int,float); //Constructor with parameters
~student(); //Deconstructors
bool get(istream &); //Input
void put(ostream &); //Output
int read_array(string,int);
private:
int id,age;
float gpa;
string last,first;
};
student::student()
{
id = 0;
first = "null";
last = "null";
age = 0;
gpa = 0.0;
}
bool student::get(istream &in)
{
in >> id >> first >> last >> age >> gpa;
return(in.good());
}
void student::put(ostream &out)
{
out << id << first << last << age << gpa;
}
When i run this It displays the constructor values over, and over and the data from the file that should be going into the array and displaying them. I am not sure if I am doing the right way to put the data into the class array correctly.

Answer 1

Here's one problem:
if (f.good())
{
// student[i] has just been read from the file.
i++; // Increment counter.
student[i].put(cout); // Print whatever was in the next element.
cout << i;
}
The counter is incremented first, so student[i] refers to the element after the one that was just updated.