Error in calling a function for a new object

[Shishykish]

Hello,

I have created a class to enter, compute and calculate grade averages. When calling the function in int main, I keep getting error messages like

for member 'EnterID_and_Grades' in 'A', which is of non-class type 'Student()'|

I am unsure where I have gone wrong.

  #include <iostream>
#include<iomanip>

using namespace std;

const int Rows = 2;
const int col = 8;
double IDandGrades [Rows][col];
//int studentID;

class Student{

public:
    //vonstructor
    Student(double IDandGrades[Rows][col]){

        for (int i = 0; i < Rows; i++)
        {
            for (int j = 0; j < col; j++)
            {
                IDandGrades[i][j] = 0;
            }
        }
    }


    void EnterID_and_Grades(double[Rows][col],int, int);
    double StudentGradeAvg(double[Rows][col]);
    void ShowIDandGrades(double[Rows][col]);

};

void Student::EnterID_and_Grades(double IDandGradeArray[Rows][col], int studentID1, int studentID2)
{
    cout << "Enter the student ID for first student" <<endl;
    cin >> studentID1;

    IDandGrades[0][0] = studentID1;

    cout << "Enter the student ID for 2nd student" <<endl;
    cin >> studentID2;

    IDandGrades[1][0] = studentID2;

    for (int i = 0; i < Rows; i++)
    {
        for (int j = 1; i < col;j++)
        {
            cout << "Enter the grade of the student" << endl;
            cin >> IDandGradeArray[i][j];
        }
    }
}

double Student::StudentGradeAvg(double IDandGradeArray[Rows][col])
{
    double total = 0;

    for (int i = 0; i < Rows; i++)
    {
        for (int j = 1; j < col-2; j++)
        {
            total+=IDandGrades[i][j];
        }
    }

    return total / 5;
}

void Student::ShowIDandGrades(double[Rows][col])
{

    cout    << "Student ID" << setw(5) << "Grade 1" << setw(5) << "Grade 2" << setw(5)
            << "Grade 3" << setw(5) << "Grade 4" << setw(5) << "Grade 5" << endl;

    for (int i = 0; i < Rows; i++)
        {
            cout << endl;

            for (int j = 0; j < col; j++)
            {
                cout << IDandGrades[i][j] << setw(5);
            }
        }
}

int main()
{
    Student A();
    Student B();

    A.EnterID_and_Grades();
    A.ShowIDandGrades();
    A.StudentGradeAvg();

    return 0;
}

[48T7M4Gy]

You need to include the constructor parameters in main to meet the requirements of your Student constructor and then the same for the various methods you call in lines 92-93

Without the parameters and a default constructor, A() is not a Student.

[48T7M4Gy]

You might consider simplifying your class and using the class to hold the grades. That way you don't need to pass them around via the functions. ie a Student 'knows' their grades. You can enter the grades the way I have shown or make it a method of the class as you have done which is just as good. The important thing is the array is a private member of the class and not external to it.

#include <string>
#include <iostream>

using namespace std;

class Student{
private:
    int grades[10]{0}; // <---
    string name;
    int ID;
    
public:
    Student(string aName, int anID);
    
    void enterGrade(int aGrade, int anIndex){ grades[anIndex] = aGrade;}
    double getAverageGrade(){/* ... */};
    void displayGrades(){/* ... */};
};



int main()
{
    Student A("Smith", 1056);
    A.enterGrade(98, 3);
    A.enterGrade(87, 2);
    
    cout << A.getAverageGrade() << endl;
    
    return 0;
}

[Shishykish]

Hello All,

Thanks very much for the solutions and alternative methodologies. This isn't for any assignments, I'm just curious about coding and picked up a few old Uni textbooks from my science degree.

I'll give these both a go!