[백준/Java] 9498번 : 시험 성적

import java.io.*;

public class Main {
    public static void main(String[] args) throws IOException {
        BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
        int a = Integer.parseInt(br.readLine());

        BufferedWriter bw = new BufferedWriter(new OutputStreamWriter(System.out));
        if (a>=90 && a<=100){
            bw.write("A");
        } else if (a>=80 && a<=89){
            bw.write("B");
        } else if (a>=70 && a<=79){
            bw.write("C");
        } else if (a>=60 && a<=69) {
            bw.write("D");
        } else{
            bw.write("F");
        }
        bw.flush();
        bw.close();
    }
}