#include <stdio.h>
int main (void) {
  char grade;
  scanf ("%c", &grade);
  if (grade == 'A') 
    printf("Excellent"); 
  else if (grade == 'B') 
    printf("Good"); 
  else if (grade == 'C') 
    printf("Average"); 
  else if (grade == 'D') 
    printf("Fair"); 
  else 
    printf("Invalid grade"); 
  return 0;
}