inheritance.cs

class Student : Person{
    private int[] testScores;  
    
    public Student(string firstName, string lastName, int identification, int[] scores) {
        this.firstName = firstName;
        this.lastName = lastName;
        this.id = identification;
        this.testScores = scores;
    }
    public string calculate() {
        double totalScore = 0;
        string returnLetter;
        for(int j = 0; j < testScores.Length; j++) {
            totalScore += testScores[j];
        }
        if(totalScore/(testScores.Length) >= 90) {
            returnLetter = "O";
        } else if(totalScore/(testScores.Length) < 90 && totalScore/(testScores.Length) >= 80) {
            returnLetter = "E";
        } else if(totalScore/(testScores.Length) < 80 && totalScore/(testScores.Length) >= 70) {
            returnLetter = "A";
        } else if(totalScore/(testScores.Length) < 70 && totalScore/(testScores.Length) >= 55) {
            returnLetter = "P";
        } else if(totalScore/(testScores.Length) < 55 && totalScore/(testScores.Length) >= 40) {
            returnLetter = "D";
        } else {
            returnLetter = "T";
        }
        return returnLetter;
    }
}