/*
 * Simple filter to average every 60 samples.
 */

#include <stdio.h>
#include <stdlib.h>

#define SAMPLES 60

void
main()
{
    long Count;
    double Sum;
    double Value;

    while (1) {
        Sum = 0.0;
        for (Count = 0; Count < SAMPLES; Count += 1) {
            if (EOF == scanf("%lf", &Value)) {
                fprintf(stderr, "Final %ld samples ignored.\n", Count);
                return;
            }
            Sum += Value;
        }
        printf("%10.6lf\n", Sum / Count);
    }
}