Someone help me please?

[FreakNasty188]

I have to write this program for class. Can anyone help me? There's like barely any work I have to do on it, it's supposed to be really easy, I'm just stuck.

/********************************************************************************************
                      10/20/11:  Graded In-Class Exercise (Due by 11:59 PM - 10/21/11)

Write a C++ program that reads a list of grades from the file grades.txt,
and finds/calculates the average and the letter grade for each student and appends the
appropriate letter grade for each student to the same data file.

Reading, writing and assigning letter grade should be performed by
appropriate functions (minimum of two functions needed).

For letter grade use the criteria that was used in class, e.g. =90 is an A, etc.

Hints:
A file can be opened for input and appended output at the same time.
When reading from a file the header line should be read outside the loop.
End of the file has been identified by "zzzzz"

********************************************************************************************/

/*********************************************
* file name:
* programmer name:
* date created:
* date of last revision:
* details of the revision:
* short description:
**********************************************/

#include <iostream>
#include <string>
#include <fstream>
using namespace std;

// Function prototypes
void instructions();
void writeFile(ofstream& outFile,
               string firstName,
               string lastName,
               char letterGrade);
void readFile(ifstream& inFile,
              string& lastName,
              float& exam1,
              float& exam2,
              float& exam3,
              float& exam4);

int main()
{
    // Program description
    instructions();

    // Declare the variables
    ifstream inFile;
    ofstream outFile;

    string firstName,
           input,
           lastName;

    float exam1,
          exam2,
          exam3,
          exam4,
          total,
          average;

    char letterGrade;

    // Open the file for reading & check for failure

	...

    // Open the file for writing in append mode & check for failure

	 ...

    // Throw out the header
    getline(inFile,input);
    outFile << endl;

    // Main calculation
    while (inFile >> firstName && firstName != "zzzzz")   //firstName is read here
    {
        // Call readFile() to read remainder of the line
        ...

        //Find the average of the grades
        ...

        // Calculate the letter grade
        if (average >= 90)
            letterGrade = 'A';
        else if (average >= 80)
            letterGrade = 'B';
        else if (average >= 70)
            letterGrade = 'C';
        else if (average >= 60)
            letterGrade = 'D';
        else
            letterGrade = 'F';

        // Write to the file by calling writeFile()
        ...
    }

    // close files
    inFile.close();
    outFile.close();

    return(0);
}

// Function implementations
void instructions()
{
    // Add more to the cout statement below
    cout << "This program will calculate the averages of the grades listed in grades.txt\n\n";
}

void writeFile(ofstream& outFile,
               string firstName,
               string lastName,
               char letterGrade)
{
    // write data to file
    ...
}

void readFile(ifstream& inFile,
              string& lastName,
              float& exam1,
              float& exam2,
              float& exam3,
              float& exam4)
{
    // read one line
	...
}

And here is the text file

Student name	Exam 1	Exam 2	Exam 3	Exam 4
Jack Nicolas     77	70	65	80
Amy Brown        55	80	85	90
Josh Simpson     88	89	92	92
Michael Lansing  65	74	68	77
Sara Palm        85	78	80	81
zzzzz

 

[gnimoctiwas]

Is what you posted something you need to incorporate or is that what you have written so far?

 

[JaminB]

Off the top of my head something like this?

#include <iostream>
#include <fstream>
using namespace std;

main()
{
float testscores;
int studentID;
float average;
double gradeOne;
double gradeTwo;
double gradeThree;
double sum=0;
int i=0;
char letterGrade;
ifstream infile;
infile.open("c:\\testscores.txt");
ofstream outFile;
outFile.open("c:\\averages.txt");
infile>>studentID;
infile>>gradeOne;
infile>>gradeTwo;
infile>>gradeThree;

while (!infile.eof())
{
i++;
average=(gradeOne+gradeTwo+gradeThree)/3;
if(average>=0 && average<60)
{
letterGrade='F';
}
if(average>=60 && average<70)
{
letterGrade='D';
}
if(average>=70 && average<80)
{
letterGrade='C';
}
if(average>=80 && average<90)
{
letterGrade='B';
}
if(average>=90 && average<=100)
{
letterGrade='A';
}
else
{
cout<<"null";
}

cout<<studentID<<": "<<gradeOne<<", "<<gradeTwo<<", "<<gradeThree<<" Average: "<<average<<" "<<letterGrade<<"\n";
infile>>studentID;
infile>>gradeOne;
infile>>gradeTwo;
infile>>gradeThree;
outFile<<"Student ID: "<<studentID<<" Average: "<<average<<" "<<letterGrade<<"\n";
sum=average+sum;


}

cout<<"Student in class: "<<i<<"\nClass Average: "<<sum/i;

infile.close();

}