백준 C++ 9498번

#include <iostream>  

using namespace std;

int main(void)
{
	int score;
	cin >> score;
	
	if (score>=90)
		cout << 'A' << endl;
	else if (score>= 80)
		cout << 'B' << endl;
	else if (score>= 70)
		cout << 'C' << endl;
	else if (score>= 60)
		cout << 'D' << endl;
	else
		cout << 'F' << endl;

		
		
				
}