public class switchPro{
	public static void main(String args[])
	{
		int score = 80;
		int scoreVal = (score + 5)/10;
		char resChar = ' ';
		switch(scoreVal){
			case 0:
				if(score<0)
					resChar = 'Q';
				else
					resChar = 'E';
			break;
			case 1:
			case 2:
			case 3:
			case 4:
			case 5:
				resChar = 'E';
			break;
			case 6:
				if(score<60)
					resChar = 'E';
				else
					resChar = 'D';
			break;
			case 7:
				resChar = 'D';
			break;
			case 8:
				resChar = 'C';
			break;
			case 9:
				resChar = 'B';
			break;
			case 10:
				if(score>100)
					resChar = 'Q';
				else
					resChar = 'A';
			break;
			default:
				resChar = 'Q';
		}
		if(resChar == 'Q')
			System.out.println("輸入的學生成績不合法");
		else
			System.out.println("輸入的學生成績等級為:"+resChar);
	}
}