#include <stdio.h>

int main(void)
{
    double input = 0.0;
    double total = 0.0;
    int inputCount = 0;
    for (inputCount; input >= 0.0; inputCount++)
    {
        total += input;
        printf("실수입력 (minus to Quit) : ");
        scanf_s("%lf ", &input);
    }
    inputCount = inputCount - 1;
    printf("평균값 : %lf \n", total / inputCount);
    return 0;
}