#include <iostream>
using namespace std;

int main() {
    
    int score;
    cin >> score;

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

    return 0;
}