/* File : example.h */

#include <vector>
#include <algorithm>
#include <functional>
#include <numeric>

double average(std::vector<int> v) {
    return std::accumulate(v.begin(),v.end(),0.0)/v.size();
}

std::vector<double> half(const std::vector<double>& v) {
    std::vector<double> w(v);
    for (unsigned int i=0; i<w.size(); i++)
        w[i] /= 2.0;
    return w;
}

void halve_in_place(std::vector<double>& v) {
    for (std::vector<double>::iterator it = v.begin(); it != v.end(); ++it)
        *it /= 2.0;
}