#include using namespace std;
int main() {
int score;
cin >> score;
if(score > 90 && score <= 100){
cout << "优秀" << endl;
}else if(score > 80 && score <= 89){
cout << "良" << endl;
}else if(score > 70 && score <= 79){
cout << "中" << endl;
}else if(score > 60 && score <= 69){
cout << "及格" << endl;
}else if(score > 0 && score <= 59){
cout << "差" << endl;
}
else{
cout << "成绩不合法" <<endl;
}
return 0;
}