#include <iostream>
using namespace std;

// Print grade for the score 
void printGrade(double score)
{
  if (score >= 90.0)
    cout << 'A' << endl;
  else if (score >= 80.0)
    cout << 'B' << endl;
  else if (score >= 70.0)
    cout << 'C' << endl;
  else if (score >= 60.0)
    cout << 'D' << endl;
  else
    cout << 'F' << endl;
}

int main()
{
  cout << "Enter a score: ";
  double score;
  cin >> score;

  cout << "The grade is ";
  printGrade(score);

  return 0;
}