#include <stdio.h>

int main()
{
    float grade, sum = 0.0;
    int gradeCount = 0;
    printf("Enter grade: ");
    while (scanf("%g", &grade) == 1) {
	sum += grade;
	++gradeCount;
	printf("Enter another grade: ");
    }
    if (gradeCount > 0) {
	printf("\nAverage: %g\n", sum/gradeCount);
    } else{
	printf("\nNo grades were entered.\n");
    }

    return 0;
}