#include <stdio.h>
#include <stdlib.h>
int main()
{
int point;
printf("請輸入數字:");
scanf("%d", &point);
if(point>=90)
printf("A\n");
else
if(point>=80)
printf("B\n");
else
if(point>=70)
printf("C\n");
else
if(point>=60)
printf("D\n");
if(point<=59)
printf("Down\n");
system("pause");
return 0;
}