成绩等级

#include <iostream>#include <cstdio>#include <iomanip>#include<cmath>using namespace std;int main(){    int s,n;    cin>>s;    n=s/10;    if(s>100||s<0)    {        return -1;    }    switch(n)    {    case 10:    case 9:        cout<<"A";        break;    case 8:        cout<<"B";        break;    case 7:        cout<<"C";        break;    case 6:        cout<<"D";        break;    default :        cout<<"E";        break;    }return 0;}

输出结果：