#include "stdio.h"
void main()
{
float score;
char grade;
printf("请输入学生成绩：");
scanf("%f",&score);
while(score>100||score<0)
{
printf("输入有误，请重输：");
scanf("%f",&score);
}
switch((int)(score/100))
{
case 10:grade='A';break;
case 9:grade='A';break;
case 8:grade='B';break;
case 7:grade='C';break;
case 6:grade='D';break;
default:grade='E';
}
printf("成绩是%5.1f,相应的等级是%c\n",score,grade);
}