// Program file:  infile4.cpp
// this program demonstrates reading data from a file
//    using global variables
#include <conio.h>
#include <iostream>
#include <fstream>

using namespace std;

// function prototypes
void heading();
void getrecord();
float calcaverage();
void writerecord();

// global variable declarations
long int ssn;
int grade1, grade2;
float average;
ifstream infile;

int main()
{
	infile.open("grade2.dat");
	heading();
	cout << setiosflags(ios::fixed) << setiosflags(ios::showpoint)
         << setprecision(1);
	getrecord();
	while (! infile.eof())
	{
		average = calcaverage();
		writerecord();
		getrecord();
	}
	getch();
	return 0;
}

void heading()
{
	cout << "SocSecNum   Grade1  Grade2  Average" << endl;
}
void getrecord()
{
	infile >> ssn >> grade1 >> grade2;
}
float calcaverage()
{
    float a = 0;
    a = (grade1 + grade2) / 2.0;
	return a;
}
void writerecord()
{
	cout << setw(9) << ssn << setw(5) << "  "
	     << setw(3) << grade1 << setw(5) << "  "
	     << setw(3) << grade2 << setw(5) << "  "
	     << setw(5) << average  << endl;
}