#include<stdio.h>

intmain()

{

floatscore;

chargrade;

printf("請輸入學生成績：");

scanf_s("%f",&score);

while(score>100||score<0)

{

printf("\n輸入有誤，請重新輸入！");

scanf_s("%f",&score);

}

switch((int)(score/10))

{

case10:

case9:grade="A";break;

case8:grade="B";break;

case7:grade="C";break;

case6:grade="D";break;

case5:

case4:

case3:

case2:

case1:

case0:grade="E";

}

printf("學生成績是%5.1f:,等級是：%C。\n",score,grade);

}