#include <iostream>
#include <cstring>

using namespace std;

//find the syntax error
int main()
{
   int grade;
   string letter;

   cout<<"Enter your final score: ";
   cin>>grade;

   if(grade < 60)
   {
      letter = F;
   }
   else if(grade < 70)
   {
      letter = D;
   }
   else if(grade < 80)
      letter = C;
   else if(grade < 90)
   {   letter = B;  }
   else
   {
      letter = A;
   }

   cout<<"Your letter grade = "<<letter<<endl;

   return 0;
}