int main()
{
	int a;

	cout << "Score? \n";
	cin >> a;

	cout << "your Score is " << a << endl;

	if (a==100) {
		cout << "Perfect Score";
	}

	if (a < 101 && a > 89) {
			cout << "Grade = A";
	}
	if (a < 90 && a > 79) {
			cout << "Grade = B";
	}
	if (a < 80 && a > 69) {
			cout << "Grade = C";
	}
	if (a < 70 && a > 59) {
			cout << "Grade = D";
	}
	if (a < 60 && a >= 9) {
			cout << "Grade = F";
	}
	cout << endl;
	system("pause");
	return 0;
}