题解 | 判断成绩等级

#include <iostream>
using namespace std;

int main() {

    int score;
    cin >> score;

    // write your code here......
    if (score < 0 || score > 100) {
        cout << "成绩不合法" << endl;
    } else {
        cout << (score < 60 ? "差" : (score < 70 ? "及格" : (score < 80 ? "中" :
                                       (score < 90 ? "良" : "优秀")))) << endl;
    }

    return 0;
}