import java.util.Scanner;
public class Test09 {
public static void main(String[] args) {
System.out.println("请输入您的学习成绩:");
@SuppressWarnings("resource")
Scanner input = new Scanner(System.in);
int score = input.nextInt();
if (score >= 90 && score <= 100) {
System.out.println("A");
} else if (score >= 60 && score <= 89) {
System.out.println("B");
} else if (score >= 0 && score < 60) {
System.out.println("C");
} else {
System.out.println("输入成绩信息错误!");
}
}
}