#include <stdio.h>

int main()  {

char grade;

scanf("%c",&grade);

switch (grade) {
   case 'A': {printf("Excellent\n");break;}
   case 'B': {printf("Good\n");break;}
   case 'C': {printf("Pass\n"); break;}
   case 'D':
   case 'F': {printf("Bad\n");break;}
   default : {printf("Not a grade\n");} 

}


return 0;
}