using namespace std;

int main() {
    
    int score;
    cin >> score;
    if(score>=90&&score<=100){
        printf("优秀");
    }
    else if(score>=80&&score<=89){
        printf("良");
    }
    else if(score>=70&&score<79){
        printf("中");
    }
    else if(score>=60&&score<69){
        printf("及格");
    }
    else if(score>=0&&score<=59){
        printf("差");
    }
    else{
        printf("成绩不合法");
    }

    // write your code here......
    

    return 0;
}