double avg1(std::vector<int> const& v) {
return 1.0 * std::accumulate(v.begin(), v.end(), 0LL) / v.size();
}
float average(std::vector<float> const& v){
if(v.empty()) return 0;
auto const count = static_cast<float>(v.size());
return std::reduce(v.begin(), v.end()) / count;
}