>>319

package java_center_test;
public class six {
public static void main(String[] args)
{

if(n == 90 || n == 80){
System.out.println("A");
}else if(n == 70){
System.out.println("B");
}else if (n == 60){
System.out.println("C");
}else{
System.out.println("D");
}