题解 | #判断成绩等级#

#include <cstdio>
#include <iostream>
using namespace std;

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