V>    constexpr static uint8_t countIndex(uint8_t entityNumber) { // обратный к countEntityNumber
V>        uint8_t idx = 0;
V>        while(countEntityNumber(idx) <= entityNumber) {
V>            idx++;
V>        }

V>        return idx-1;
V>    }

V>    template<typename TOther, uint64_t MaskOther>
V>    constexpr auto operator +(const SparseArray<TOther, MaskOther>& other) const {
V>        using Result = SparseArray<decltype(T{} + TOther{}), Mask | MaskOther>;

V>        return [this, other]<uint8_t... EntityNumbers>(std::integer_sequence<uint8_t, EntityNumbers...>)
V>        {
V>            return Result{(get<Result::countIndex(EntityNumbers)>() + other.template get<Result::countIndex(EntityNumbers)>())...};
V>        }(std::make_integer_sequence<uint8_t, Result::size>{});
V>    }
V>