class Student :  public Person{
	private:
		vector<int> testScores;  
	public:
     
           Student(string firstName, string lastName,int identification,vector<int> scores)
                :Person(firstName,lastName,identification){
                this->testScores=scores;
            }
       
     char calculate(){
        int sum=0;
        for(int i=0;i<testScores.size();i++){
            sum+=testScores[i];
        }
        int avg=sum/testScores.size();
         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';
        } 
    }
};