#include<stdio.h>
main()
{
int a;
printf("请输入成绩:");
scanf("%d\n",&a);
switch(a/10)
{
case 10:
case 9:
printf("优\n");
break;
case 8:
printf("良\n");
break;
case 7:
printf("中\n");
break;
case 6:
printf("及格\n");
break;
default:
printf("不及格\n");
break;
}
}