import java.util.Scanner;
public class NewMain {

    /**
     * @param args the command line arguments
     */
    
    public static void main(String[] args) {
        // TODO code application logic here
       Scanner klavye=new Scanner(System.in); 
        System.out.println("Notu giriniz");
        int not=klavye.nextInt(); 
      
        
            if (not>90) {    
            System.out.println("AA");
            }
            else if (not>85) {    
            System.out.println("BA");
            }
            else if (not>80) {    
            System.out.println("BB");
            }
            else if (not>75) {    
            System.out.println("CB");
            }
            else if (not>50) {    
            System.out.println("Kosullu Gectiniz");
            }
           
            else{
            System.out.println("Kaldınız");
        }
    }
}