class Student extends Person{
	private int[] testScores;
    
    Student(String firstName, String lastName, int id, int[] scores){
        super(firstName, lastName, id);
        this.testScores = scores;
    }

    char calculate() {
        int myScore = 0;
        for(int i : testScores) myScore += i;
        myScore /= testScores.length;

        char myResult = (
          (myScore>=90)?'O':
          (myScore>=80)?'E':
          (myScore>=70)?'A':
          (myScore>=55)?'P':
          (myScore>=40)?'D':
          'T'
        );
        
        return(myResult);
    }
    
}