// Lokessh
// Noor Arinie binti Norhalil 
#include <iostream>
using namespace std ;

char getGrade(int mark);

int main()
{
	int assessment ;
	double mark , sum , average ;
	char grade ;
	
	cout << "Enter the number of assessments: ";
    cin >> assessment ;
    
	for (int n = 1; n <= assessment; n++)
    {
    	cout << "Enter mark of assessment " << n << " (between 1-100):" ;
        cin >> mark;
        sum = sum + mark; 
    }
    
    //cout << "Sum : " << sum << endl ;
    
    average = sum / 3.0 ;
    //cout << "Average : " << average ;
    
    grade = getGrade(average);
    cout << "The grade is " << grade << endl ;
    
    return 0 ;
}

char getGrade(int mark)
{
	char grade ;
	if (mark >= 90 && mark <= 100)
		grade = 'A' ;
	else if (mark >= 80 && mark <= 89)
		grade = 'B' ;
	else if (mark >= 70 && mark <= 79)
		grade = 'C' ;
	else if (mark >= 60 && mark <=69)
		grade = 'D' ;
	else 
		grade = 'F' ;
		
	return grade ;
}