9498번 - 시험 성적 const fs=require('fs'); const input=fs.readFileSync('/dev/stdin').toString(); const score=parseInt(input); if (score>=90){ console.log('A'); } else if (score>=80){ console.log('B'); } else if (score>=70){ console.log('C'); } else if (score>=60){ console.log('D'); } else{ console.log('F'); }