class Student extends Person{
	private int[] testScores;

    /*	
    *   Class Constructor
    *   
    *   @param firstName - A string denoting the Person's first name.
    *   @param lastName - A string denoting the Person's last name.
    *   @param id - An integer denoting the Person's ID number.
    *   @param scores - An array of integers denoting the Person's test scores.
    */
    // Write your constructor here
    Student(String firstName,String lastName,int id,int[] scores){
        super(firstName,lastName,id);
        this.testScores=scores;
    }

    /*	
    *   Method Name: calculate
    *   @return A character denoting the grade.
    */
    // Write your method here
    public char calculate(){
        int sum=0;
        for(int i=0;i<testScores.length;i++){
            sum+=testScores[i];
        }
        int avg=sum/testScores.length;
         if(90<=avg && avg<=100){
            return 'O';
        }else if(80<=avg && avg<90){
            return 'E';
        }else if(70<=avg && avg<80){
            return 'A';
        }else if(55<=avg && avg<70){
            return 'P';
        }else if(40<=avg && avg<55){
            return 'D';
         }else {
            return 'T';
        } 
    }
}