#include <stdio.h>

int main(void){

	int Math,Eng,Sci,Sum;
	double Ave;
	
	printf("Input your scores:\n");
	printf("Math:");
	scanf("%d",&Math);
	printf("English:");
	scanf("%d",&Eng);
	printf("Science:");
	scanf("%d",&Sci);

	Sum = Math+Eng+Sci;
	Ave = (double) Sum/3;
	if(Sum>=270) printf("Your grade is A++ (Average is %f)\n", Ave);
	if(Sum>=240 && Sum<=269) printf("Your grade is A (Average is %f)\n", Ave);
	if(Sum>=210 && Sum<=239) printf("Your grade is B (Average is %f)\n", Ave);
	if(Sum>=180 && Sum<=209) printf("Your grade is C (Average is %f)\n", Ave);
	if(Sum<=179) printf("Your grade is F (Average is %f)\n", Ave);
	
	return 0;

}