scale_to_smallest.cpp

std::vector v = ...;
auto min = std::ranges::min_element(v);
std::ranges::for_each(v, [&] (auto& e) { e /= min; });

std::vector v = ...;
auto min = std::ranges::min_element(v);
std::ranges::transform(v, v.begin(), [&] (auto e) { return e / min; });

std::vector v = ...;
auto min = std::ranges::min_element(v);
for (auto& e : v) e /= min;

std::vector v = ...;
auto min = std::ranges::min_element(v);
for (std::size_t i = 0; i < v.size(); ++i) e[i] /= min;