#include <stdio.h>
int main()
{
    int score = 87; //考试分数为87分
   
    switch(score)
    {
        case 10:
        case 9:score>=90 && score<=100;
            printf("等级A");
           
        case 8:score>=80 && score<90;
            printf("等级B");
                            //这里是不是缺点什么？           
        case 7:
        case 6: score>=60 && score<80;
            printf("等级C");
                            //这里是不是缺点什么？ 
        default:score<60;
            printf("等级D");
            break;   
    }
    return 0;
}