#include <stdio.h>

int main()
{
   int score;
   char grade;

   printf("Enter test score: ");
   scanf("%d", &score);

   if (score >= 90)
	grade = 'A';
   else if (score >= 80)
	grade = 'B';
   else if (score >= 70)
	grade = 'C';
   else if (score >= 60)
	grade = 'D';
   else
	grade = 'F';

   printf("The student's letter grade is: %c\n", grade);

   return 0;
}