编辑代码

#include <iostream>
using namespace std;
int main() {
    int a;
    cin >> a;
    if (a >= 90&&a <= 100){
        cout <<"A";
    }else if (a >= 80&&a <= 90){
        cout <<"B";
    }else if (a >= 70&&a <= 80){
        cout <<"C";
    }else if (a >= 60&&a <= 70){
        cout <<"D";
    }else if (a >= 0&&a <= 60){
        cout <<"E";
    }else{
        cout <<"Score is error!";
    }
	return 0;
}