#include <stdio.h>
int main()
{
int grade;
scanf("%d",&grade);
printf("Your score:");
{
if (grade>90&&grade<101)
printf("A\n");
else if(grade>80&&grade<91)
printf("B\n");
else if(grade>70&&grade<81)
printf("C\n");
else if(grade>60&&grade<71)
printf("D\n");
else if(grade<=60)
printf("E\n");;
}
return 0;
}