Question

In C++

The existing code provides number of students who get A grade ( >=91 ), their average points. You may need to provide code for other students who got B, C, D and F grades with grade >= 81, 71, 61 and below 61 respectively. You are asked to write a print function to display / print name of group ( such as Grade A group) , number, and average grade. in the main function, you just make the function call for each group of students.

You may be asked to write a function to translate average point of class to letter grade. For example, when average point of class is 82.45, the overall letter grade of class is B

You may be asked to provide statistics how many input, and how many errors are there ?

Below is code that needs to be updated with above information

#include <iostream>
#include <string>
#include <iomanip>

using namespace std;

int main()
{


        const int MAX_GRADE = 100;
        const int A_GRADE = 91;                 // Grad A's points

        int countGradeA = 0;                    // number of Grade A students
        double totalGradeA = 0.;                // total points of Grade A students


        int counter = 0;        // number of students
        int grade;                      // student's grade; must be positive and <= MAX_GRADE
        double average;         // grade average
        double total = 0;       // total grades

        while (true)  {

                cout << "Enter grade, Ctr-Z (Windows) / Ctr-D ( Unix) to end : ",
                cin >> grade;

                if ( cin.fail()) {
                        if ( cin.eof()) {
                                cout << "Finish entering data !" << endl;
                                break;
                        } else
                        {
                                string error;
                                cin.clear();
                                cin >> error;
                                cout << error << " Wrong data type " << endl;
                        }
                } else if ( grade < 0 || grade > MAX_GRADE) {
                        cout << grade << " Wrong data, must be positive and <= " << MAX_GRADE << endl;
                } else {
                        total += grade;
                        counter++;
                        cout << grade << endl;
                        if ( grade >= A_GRADE)
                        {
                                countGradeA++;
                                totalGradeA += grade;
                        }
                }

        }

        // compute an average of grades
    cout << fixed << setprecision(2);
        if ( counter > 0) 
        {
                average = total / counter;
                cout << setw(20) << "Total students:   " << setw(10) << counter <<  setw(10) << "Average: " << setw(10) << average << endl;

        } else {
                cout << "No grade entered " << endl;
        }
        if (countGradeA > 0) {
           cout << setw(20) << "Grade A Students: " << setw(10) << countGradeA 
                << setw(10) << " Average: " << setw(10) << totalGradeA / countGradeA << endl;
        }


        return 0;
}

Answer 1

Note: Could you plz go through this code and let me know if u need any changes in this.Thank You
=================================

#include <iostream>
#include <string>
#include <iomanip>

using namespace std;

string letterGrade(double average);
int main()
{

const int MAX_GRADE = 100;
const int A_GRADE = 91; // Grad A's points
const int B_GRADE = 81;
const int C_GRADE = 71;
const int D_GRADE = 61;

  

int countGradeA = 0; // number of Grade A students
double totalGradeA = 0.; // total points of Grade A students

int countGradeB = 0; // number of Grade A students
double totalGradeB = 0.; // total points of Grade A students
  
int countGradeC = 0; // number of Grade A students
double totalGradeC = 0.; // total points of Grade A students
  
int countGradeD = 0; // number of Grade A students
double totalGradeD = 0.; // total points of Grade A students
  
int countGradeF = 0; // number of Grade A students
double totalGradeF = 0.; // total points of Grade A students

int counter = 0; // number of students
int grade; // student's grade; must be positive and <= MAX_GRADE
double average; // grade average
double total = 0; // total grades

while (true)
{

cout << "Enter grade, Ctr-Z (Windows) / Ctr-D ( Unix) to end : ", cin >> grade;

if (cin.fail())
{
if (cin.eof())
{
cout << "Finish entering data !" << endl;
break;
}
else
{
string error;
cin.clear();
cin >> error;
cout << error << " Wrong data type " << endl;
}
}
else if (grade < 0 || grade > MAX_GRADE)
{
cout << grade << " Wrong data, must be positive and <= " << MAX_GRADE << endl;
}
else
{
total += grade;
counter++;
cout << grade << endl;
if (grade >= A_GRADE)
{
countGradeA++;
totalGradeA += grade;
}
else if (grade >= B_GRADE)
{
countGradeB++;
totalGradeB += grade;
}
else if (grade >= C_GRADE)
{
countGradeC++;
totalGradeC += grade;
}
else if (grade >= D_GRADE)
{
countGradeD++;
totalGradeD += grade;
}
else if (grade <D_GRADE)
{
countGradeF++;
totalGradeF += grade;
}
}
}

// compute an average of grades
cout << fixed << setprecision(2);
if (counter > 0)
{
   string gradeLetter;
average = total / counter;
gradeLetter= letterGrade(average);

cout << setw(20) << "Total students: " << setw(10) << counter << setw(10)
<< "Average: " << setw(10) << average << endl;
cout<<"Overall Grade Letter :"<<gradeLetter<<endl;
}
else
{
cout << "No grade entered " << endl;
}
if (countGradeA > 0)
{
cout << setw(20) << "Grade A Students: " << setw(10) << countGradeA << setw(10)
<< " Average: " << setw(10) << totalGradeA / countGradeA << endl;
}
if (countGradeB > 0)
{
cout << setw(20) << "Grade B Students: " << setw(10) << countGradeB << setw(10)
<< " Average: " << setw(10) << totalGradeB / countGradeB << endl;
}
if (countGradeC > 0)
{
cout << setw(20) << "Grade C Students: " << setw(10) << countGradeC << setw(10)
<< " Average: " << setw(10) << totalGradeC / countGradeC << endl;
}
if (countGradeD > 0)
{
cout << setw(20) << "Grade D Students: " << setw(10) << countGradeD << setw(10)
<< " Average: " << setw(10) << totalGradeD / countGradeD << endl;
}
if (countGradeF > 0)
{
cout << setw(20) << "Grade F Students: " << setw(10) << countGradeF << setw(10)
<< " Average: " << setw(10) << totalGradeF / countGradeF << endl;
}

return 0;
}
string letterGrade(double average)
{
   string gradeLetter;
   if (average >= 90 && average<=100)
gradeLetter = 'A';
else if (average >= 80 && average < 90)
gradeLetter = 'B';
else if (average >= 70 && average < 80)
gradeLetter = 'C';
else if (average >= 60 && average < 70)
gradeLetter = 'D';
else if (average < 60)
gradeLetter = 'F';
return gradeLetter;
}

=====================================

Output:

===================================Thank You