Function ExtremeElementBy

util/generic/algorithm.h:16–33

namespace NPrivate {
    template <class I, class F, class P>
    constexpr I ExtremeElementBy(I begin, I end, F&& func, P&& pred) {
        if (begin == end) {
            return end;
        }

        auto bestValue = func(*begin);
        auto bestPos = begin;

        for (++begin; begin != end; ++begin) {
            auto curValue = func(*begin);
            if (pred(curValue, bestValue)) {
                bestValue = std::move(curValue);
                bestPos = begin;
            }
        }

        return bestPos;
    }
} // namespace NPrivate

template <class T>