char 不是单个字符吗？    %f 不是单浮点标量吗,,,,

#include<stdio.h>

 main()

 {

int grade;

printf("\ninput grade:");

scanf("%d",&grade);

grade=int(grade/10);

switch(grade)

{

case 10:

case 9:printf("\n A");break;

case 8:printf("\n B");break;

case 7:printf("\n C");break;

case 6:printf("\n D");break;

default:printf("\n E");break;

}

 

}