---

decision.c:
int make_decision(double *data, int n)
{
    int decision = 1;

    double m = mean(data, n);
    double sigma = sqrt(variance(data, n));
    double max_value = max(data, n);
    double min_value = min(data, n);

    decision &= (max_value <= m + 3*sigma) &&
                (max_value >= m - 3*sigma) &&
                (m >= GOLDEN_RATIO);

    return decision;
}
s

decision.h:
#define GOLDEN_RATIO 0.618

yet_another_decision_module_entry.c:
void main()
{
    double *data;
    int n;
    
    if (make_decision(data, n))
        printf("YES"); 
    else
        printf("NO");  
}