public static void main(String[] args) {
        Scanner in = new Scanner(System.in);
        char grade = in.next().charAt(0);
        switch (grade) {
            case 'A':
                System.out.println("Excellent");
            case 'B':
                System.out.println("Good");
            case 'C':       
                System.out.println("So so");
            case 'D':
                System.out.println("Fails");
            case 'F':
                System.out.println("Get lost");
            default:
                System.out.println("Invalid");
        }
    }