C++ Array Project

#include<iomanip>
#include<iostream>
#include<fstream>
#include<cstdlib>
#include<cctype>

using namespace std;
const int max_students = 7;

class Student
{
private:
    char studentname[30];
    int projgrade[6];
    int examgrade[2];
    int quizgrade[9];
    int finalgrade;
    double projavg;
    double examavg;
    double quizavg;
    double totalavg;
    char grade[30];
public:
    Student();
    ~Student();

    void get_student_scores();
    void compute_student_stats();
    void determine_student_grade();
    void display_student_name_gpa_grade();
    double student_average();
};

class Course
{
private:
    Student student[max_students];
    int highest;
    int lowest;
public:
    Course();
    ~Course();

    void get_grades();
    void evaluate_class();
    void determine_index_of_highest_lowest();
    void display_highest();
    void display_lowest();
    void display_stats();
};

    const double projectweight = 0.25,
                 quizweight = 0.10,
                 examweight = 0.15,
                 finalweight = 0.20;


int main()
{
    Course the_course;

    void describe_program();

    describe_program();

    the_course.get_grades();
    the_course.evaluate_class();
    the_course.determine_index_of_highest_lowest();
    the_course.display_stats();
    the_course.display_highest();
    the_course.display_lowest();

   system("PAUSE");
   return 0;
}

void describe_program()
{
cout<<"This program will prompt for the names of seven students, and for each \n";
cout<<"student, prompt for the various grades that student has received. \n";
cout<<"The program will also calculate averages for each grade, as well as \n";
cout<<"the student with the highest and student with the lowest class average. \n";
cout<<"All results will be printed to the screen and sent to an external text \n";
cout<<"file, 'grades.txt'.";
cout<<endl<<endl;
}




///////////////////////////////////////////////////////////////////////////////
//                          "Student" Functions                              //
///////////////////////////////////////////////////////////////////////////////

Student::Student()
{
    studentname[30] = '\0';
    projgrade[0] = 0;
    examgrade[0] = 0;
    quizgrade[0] = 0;
    finalgrade = 0;
    projavg = 0;
    examavg = 0;
    quizavg = 0;
    totalavg = 0;
    grade[30] = '\0';
}

Student::~Student()
{
   cout<<"Student object going out of existence!\n";
   system("PAUSE");
}

void Student::get_student_scores() //Enter grades for the student
{
     int i;

     cout<<"Enter the name of the student: ";
     cin.getline(studentname,30);
     cout<<endl<<endl;

     for(i=0; i<7; i++) //Enter project grades
        {
        cout<<"Enter the grade for Project "<<i+1<<":";
        cin>>projgrade[i];
        cout<<endl;
        while(projgrade[i] > 100 || projgrade[i] < 0)
         {
          cout<<"Illegal grade entered!"<<endl;
          cout<<"Enter the grade for Project "<<i+1<<":";
          cin>>projgrade[i];
          cout<<endl;
         };
        }
        cout<<endl;

     for(i=0; i<3; i++) //Enter exam grades
        {
        cout<<"Enter the grade for Exam "<<i+1<<":";
        cin>>examgrade[i];
        cout<<endl;

        while(examgrade[i] > 100 || examgrade[i] < 0)
        {
          cout<<"Illegal grade entered!"<<endl;
          cout<<"Enter the grade for Exam "<<i+1<<":";
          cin>>examgrade[i];
          cout<<endl;
         };
        }
        cout<<endl;

     for(i=0; i<10; i++) //Enter quiz grades
        {
        cout<<"Enter the grade for Quiz "<<i+1<<":";
        cin>>quizgrade[i];
        cout<<endl;

        while(quizgrade[i] > 100 || quizgrade[i] < 0)
         {
          cout<<"Illegal grade entered!"<<endl;
          cout<<"Enter the grade for Quiz "<<i+1<<":";
          cin>>quizgrade[i];
          cout<<endl;
         };
        }
        cout<<endl;

        cout<<"Enter the grade for the Final Exam:";
        cin>>finalgrade;
        while(finalgrade > 100 || finalgrade < 0)
         {
          cout<<"Illegal grade entered!"<<endl;
          cout<<"Enter the grade for Final Exam:";
          cin>>finalgrade;
          cout<<endl;
         };
        cout<<endl<<endl;

}

void Student::compute_student_stats() //Calculates averages
{
     int i, sum;
     double temp;

       //Calculate project average

       sum = 0;
       for(i=0; i<6;i++)
          sum += projgrade[i];
       temp = static_cast<double>(sum)/6;
       projavg = static_cast<int>(temp + 0.5);

       //Calculate exam average

       sum = 0;
       for(i=0;i<3;i++)
          sum += examgrade[i];
       temp = static_cast<double>(sum)/2;
       examavg = static_cast<int>(temp + 0.5);

       //Calculate quiz average

       sum = 0;
       for(i=0;i<10;i++)
          sum += quizgrade[i];
       temp = static_cast<double>(sum)/5;
       quizavg = static_cast<int>(temp + 0.5);

}

void Student::determine_student_grade() //Determines total grade and letter grade
{

     totalavg = projavg * projectweight +
                quizavg    * quizweight +
                examavg    * examweight +
                finalgrade * finalweight;

       grade[0] = ' ';
       grade[1] = ' ';
       if(totalavg>=93)
       {
            grade[0] = 'A';
            grade[1] = ' ';
       }
       else if(totalavg>=89)
       {
            grade[0] = 'A';
            grade[1] = '-';
       }
       else if(totalavg>=87)
       {
            grade[0] = 'B';
            grade[1] = '+';
       }
       else if(totalavg>=83)
       {
            grade[0] ='B';
            grade[1] = ' ';
       }
       else if(totalavg>=79)
       {
            grade[0] = 'B';
            grade[1] = '-';
       }
       else if(totalavg>=77)
       {
            grade[0] = 'C';
            grade[1] = '+';
       }
       else if(totalavg>=73)
       {
            grade[0] = 'C';
            grade[1] = ' ';
       }
       else if(totalavg>=69)
       {
            grade[0] = 'C';
            grade[1] = '-';
       }
       else if(totalavg>=67)
      {
            grade[0] = 'D';
            grade[1] = '+';
      }
      else if(totalavg>=63)
      {
            grade[0] = 'D';
            grade[1] = ' ';
      }
      else if(totalavg>=57)
      {
            grade[0] = 'D';
            grade[1] = '-';
      }
    else
     {
           grade[0] = 'F';
           grade[1] = ' ';
     }

}

void Student::display_student_name_gpa_grade() //Display results to screen and text file
{
     cout<<"Student name: "<<studentname<<endl;
     cout<<"Semester Average: "<<totalavg<<endl;
     cout<<"Grade: "<<grade[0]<<grade[1]<<endl;

     //Send to text file

     ofstream outs;
     outs.open("grades.txt",ios::app);

     outs<<"Student name: "<<studentname<<endl;
     outs<<"Semester Average: "<<totalavg<<endl;
     outs<<"Grade: "<<grade<<endl;

     outs.close();

}

double Student::student_average() //Returns average grade for one student
{
 return totalavg;
}



///////////////////////////////////////////////////////////////////////////////
//                          "Course" Functions                               //
///////////////////////////////////////////////////////////////////////////////


Course::Course() //Initialize highest grade and lowest grade subscripts
{
 highest = 0;
 lowest = 0;
}

Course::~Course()
{
   cout<<"Course object going out of existence!\n";
   system("PAUSE");
}

void Course::get_grades() //Tells user what student # to enter data for
{
     int i;

     for(i=0; i<7; i++)
     {
     cout<<"Enter data for student #"<<i+1<<endl;
     student[i].get_student_scores();
     cin.ignore();
     }
}

void Course::evaluate_class() //Calculates grades for all students
{
     int i;

     for(i=0; i<7; i++)
     {
     student[i].compute_student_stats();
     student[i].determine_student_grade();
     }
}

void Course::determine_index_of_highest_lowest() //Finds highest and lowest grade in class.
{
    double max;
    double tempgrade;
    max = 0;
    tempgrade = 0;

    for(int i=0; i<7; i++)
    {
          tempgrade = student[i].student_average();
          if(tempgrade>max)
          {
          highest = i;
          max = tempgrade;
          }
    }

    max = 101;
    tempgrade = 0;

    for(int i=0; i<7; i++)
    {
          tempgrade = student[i].student_average();
          if(tempgrade<max)
          {
          lowest = i;
          max = tempgrade;
          }
    }
}

void Course::display_stats() //Displays all student info on screen
{
     int i;

   for(i=0; i<7; i++)
   student[i].display_student_name_gpa_grade();

}

void Course::display_highest() //Displays student with highest grade
{
     ofstream outs;
     outs.open("grades.txt",ios::app);

     cout<<"\n\nThe highest grade in the class was: \n";
     outs<<"\n\nThe highest grade in the class was: \n";

     outs.close();

     student[highest].display_student_name_gpa_grade();
}

void Course::display_lowest() //Displays student with lowest grade
{
     ofstream outs;
     outs.open("grades.txt",ios::app);

     cout<<"\n\nThe lowest grade in the class was: \n";
     outs<<"\n\nThe lowest grade in the class was: \n";

     outs.close();

     student[lowest].display_student_name_gpa_grade();
}