(C++) - 백준(BOJ) 9498번 : 시험성적 답

#include <iostream>
using namespace std;
int main(){
 int n=0;
 cin>>n;
if(90<=n&&n<=100)
 cout<<"A";
else if(80<=n&&n<=89)
 cout<<"B";
else if(70<=n&&n<=79)
 cout<<"C";
else if(60<=n&&n<=69)
 cout<<"D";
else
 cout<<"F";
}